Patent Publication Number: US-11662163-B2

Title: Bolt action AR rifle

Description:
CROSS-REFERENCE 
     This patent application is a continuation of U.S. application Ser. No. 16/818,960 filed Mar. 13, 2020, which is a continuation-in-part of U.S. application Ser. No. 15/666,230 filed Aug. 1, 2017 now U.S. Pat. No. 10,627,177, which claims priority to U.S. Provisional Application No. 62/373,499 filed Aug. 11, 2016, which provisional is incorporated herein by specific reference in its entirety. 
    
    
     BACKGROUND 
     Often, rifle sportsmen enjoy shooting guns of different types and different calibers. However, one gun is often of a single type and of a single caliber. As such, the rifle sportsman has to obtain multiple guns in order to have different types and/or different calibers. While it may be favorable to have different types of guns, the rifle sportsman is forced into buying multiple guns. 
     Therefore, it would be advantageous to be able to have a gun that converts from a first type to a second type. 
     SUMMARY 
     In some embodiments, a bolt can be configured for being included in a bolt action upper receiver of a bolt action upper receiver assembly. The bolt action upper receiver assembly can be configured to be coupled to a standard AR lower receiver assembly. The bolt can include a unitary body having: a bolt head having three bolt lungs extending outward relative to three bolt reliefs that are located between the bolt lungs, wherein one bolt lug includes an extractor slot extending radially from a bolt head recess all the way through the one bolt lug. The unitary bolt body can be elongate and having: a bullet pushing ridge extending from a bolt neck to a bolt end opposite of the bolt head, the bullet pushing ridge having a height and length relative to the bolt body; a bullet pushing slope extending downward from the bullet pushing ridge toward the bolt end and terminating at a hammer pushing ridge; the hammer pushing ridge extending from the bullet pushing slope to an end slot; an end ramp across the end slot from the hammer pushing ridge, the end ramp extending upward; an end ridge extending from a top of the end ramp; and a firing pin recess at the bolt end extending toward the bolt head, wherein the firing pin recess includes an opening from the bolt end around the end ramp and end ridge so as to be open with the end slot, wherein the bolt neck is connecting the bolt head with the bolt body, the bolt neck being thinner than the bolt body. In one aspect, the bullet pushing ridge, bullet pushing slope, hammer pushing ridge, end slot, end ramp and end ridge are longitudinally aligned with one of the bolt lugs. In one aspect, the unitary body has a first body portion of the bolt body extending from the bolt neck toward the bolt end and terminating at a magazine recess that has a shape commensurate with a magazine with a second body portion extending from the magazine recess to the bolt end. In one aspect, the first body portion, magazine recess and second body portion are longitudinally aligned. In one aspect, the first body portion, magazine recess and second body portion are longitudinally aligned with the one bolt lung that has the extractor slot, and wherein the second body portion is separated from the end ridge by the firing pin recess. In one aspect, the unitary body has a bolt handle recess in the second body portion offset from the magazine recess, the bolt handle recess extending into the firing pin recess. In one aspect, the first body portion and second body portion are portions of a cylindrical portion of the unitary body, which cylindrical portion extends from a first side of a base of the bullet pushing ridge and first side of a base of the end ridge around to a second side of the base of the bullet pushing ridge and second side of the base of the end ridge. In one aspect, the cylindrical portion includes a roll pin hole and a nut relief. In one aspect, the hammer pushing ridge has a higher elevation than the end ridge. 
     In some embodiments, a bolt action upper receiver can be configured to be coupled with a standard AR lower receiver. The bolt action upper receiver can include a unitary receiver body having a receiver lumen and a top; a proximal end having a bolt opening; a distal end having a barrel opening surrounded by a threaded receiver with a dowel pin receiver in a distal end of the threaded receiver, the dowel pin receiver being axially oriented; a bottom comprising: a magazine slot open to and longitudinally aligned with a hammer slot, the hammer slot being narrower than the magazine slot; a takedown pin receiver hole at a proximal end, the takedown pin receiver hole being orthogonal with the magazine slot and hammer slot; and a pivot pin receiver hole at a distal end, the pivot pin receiver hole being orthogonal with the magazine slot and hammer slot, the pivot pin receiver hole being parallel with the takedown pin receiver hole; a first side having: a bolt handle slot extending from the bolt opening and exposing a portion of the receiver lumen; a bolt rest slot extending from the bolt handle slot; an ejection port between the bolt handle slot and distal end; and a second side having a magazine release receiver recess. In one aspect, the bolt action upper receiver can include an extractor ramp that defines an end of the bolt handle slot that intersects with the bolt rest slot. In one aspect, the bolt action upper receiver can include a picatinny rail on the top. In one aspect, the bolt action upper receiver can include the bottom comprising a pivot pin body having the pivot pin receiver hole and a takedown pin body having the takedown pin receiver hole. 
     In some embodiments, a bolt action upper receiver assembly can include: a bolt action upper receiver configured to be coupled with a standard AR lower receiver, the bolt action upper receiver comprising a unitary receiver body having a receiver lumen, the unitary receiver body having: a top; a proximal end having a bolt opening; a distal end having a barrel opening surrounded by a threaded receiver with a dowel pin receiver in a distal end of the threaded receiver, the dowel pin receiver being axially oriented; a bottom comprising: a magazine slot open to and longitudinally aligned with a hammer slot, the hammer slot being narrower than the magazine slot; a takedown pin receiver hole at a proximal end, the takedown pin receiver hole being orthogonal with the magazine slot and hammer slot; and a pivot pin receiver hole at a distal end, the pivot pin receiver hole being orthogonal with the magazine slot and hammer slot, the pivot pin receiver hole being parallel with the takedown pin receiver hole; a first side having: a bolt handle slot extending from the bolt opening and exposing a portion of the receiver lumen; a bolt rest slot extending from the bolt handle slot; and an ejection port between the bolt handle slot and distal end; a second side having a magazine release receiver recess; and a bolt slidably located in the receiver lumen, the bolt comprising a unitary body having: a bolt head having three bolt lungs extending outward relative to three bolt reliefs that are located between the bolt lungs, wherein one bolt lug includes an extractor slot extending radially from a bolt head recess all the way through the one bolt lug; a bolt body being elongate and having: a bullet pushing ridge extending from a bolt neck to a bolt end opposite of the bolt head, the bullet pushing ridge having a height and length relative to the bolt body; a bullet pushing slope extending downward from the bullet pushing ridge toward the bolt end and terminating at a hammer pushing ridge; the hammer pushing ridge extending from the bullet pushing slope to an end slot; an end ramp across the end slot from the hammer pushing ridge, the end ramp extending upward; and an end ridge extending from a top of the end ramp; and a firing pin recess at the bolt end extending toward the bolt head, wherein the firing pin recess includes an opening from the bolt end around the end ramp and end ridge so as to be open with the end slot, wherein the bolt neck is connecting the bolt head with the bolt body, the bolt neck being thinner than the bolt body. In one aspect, the bullet pushing ridge, bullet pushing slope, hammer pushing ridge, end slot, end ramp and end ridge are longitudinally aligned with one of the bolt lugs, and which are oriented toward the bottom of the bolt action upper receiver in a firing orientation. In one aspect, the unitary body having a first body portion of the bolt body extending from the bolt neck toward the bolt end and terminating at a magazine recess that has a shape commensurate with a magazine with a second body portion extending from the magazine recess to the bolt end, wherein the first body portion, magazine recess and second body portion are longitudinally aligned, wherein the magazine recess is oriented toward the bottom of the bolt action upper receiver in a loading orientation. In one aspect, the unitary body having a bolt handle recess in the second body portion offset from the magazine recess, the bolt handle recess extending into the firing pin recess, a bolt handle located in the bolt handle recess, the bolt handle: extending out of the bolt handle slot during the loading orientation; and extending out of the bolt rest slot during the firing orientation. In one aspect, the bolt action upper receiver comprising an extractor ramp that defines an end of the bolt handle slot that intersects with the bolt rest slot. In one aspect, the bolt action upper receiver comprising a picatinny rail on the top. 
     In some embodiments, a method of forming a bolt action AR rifle can include: providing the bolt action upper receiver assembly of one of the embodiments; providing a standard AR lower receiver assembly having a pivot pin and takedown pin; inserting the pivot pin into the pivot pin receiver hole; pivoting the bolt action upper receiver assembly at the pivot pin until the takedown pin is aligned with the takedown pin receiver hole; and inserting the takedown pin into the takedown pin receiver hole. 
     In some embodiments, a bolt can be configured for being included in a bolt action upper receiver of a bolt action upper receiver assembly, wherein the bolt action upper receiver assembly is configured to be coupled to a standard AR lower receiver assembly. The bolt can include a unitary body having in a longitudinal axis and a longitudinal sequence that includes the following: a bullet pushing ridge extending from a neck toward a bolt tail, the bullet pushing ridge having a first height relative to the bolt body; a bullet pushing slope with a negative taper from the height of the bullet pushing ridge and terminating at a reduced dimension region having a hammer pushing surface extending from the bullet pushing slope to an end slot; an end ramp across the end slot from the hammer pushing ridge, the end ramp extending upward; an end ridge extending from a top of the end ramp to the bolt tail; and a firing pin recess in the bolt end, wherein the firing pin recess includes an opening from the bolt end around the end ramp and end ridge so as to be open with the end slot. In some aspects, the bullet pushing ridge, bullet pushing slope, hammer pushing surface, end slot, end ramp and end ridge are longitudinally aligned with a bolt lug at a tip of the bolt. In some aspects, the unitary body can have a first body portion of the bolt body extending from the bolt neck and terminating at the reduced dimension region, and can have a second body portion extending from the reduced dimension region to the bolt end. 
     In some embodiments, the first body portion has the first height with at least two grooves formed therein to define the bullet pushing ridge. In some aspects, the reduced dimension region has a second height that is less than the first height. In some aspects, the second body portion has a region with a third height that is larger than the second height and has a planar surface with the second height. In some aspects, the reduced dimension region is a cylindrical region. In some aspects, the cylindrical region includes a cylindrical surface, which includes a portion thereof that functions as the hammer pushing surface. In some aspects, the first body portion and second body portion include larger dimensioned cylindrical portions of the unitary body, which larger dimensioned cylindrical portions each extends longitudinally from the reduced dimension region. In some aspects, the cylindrical region is devoid of recesses or elevations between the bullet pushing slope and end slot. In some aspects, the hammer pushing surface has a same elevation than the end ridge. 
     In some embodiments, the bolt can include a second longitudinal sequence of elements, which second longitudinal sequence can be along a longitudinal axis or longitudinal surface region of the bolt. That is, the above recited longitudinal sequence can be considered the first longitudinal sequence. The sequence is not linear, provided in a sequence order from the tip to the tail of the bolt. In some aspects, the second longitudinal sequence that is aligned (e.g., somewhat parallel) and separate with the first longitudinal sequence can include: a head region lateral of the bullet pushing ridge and having a taper surface lateral of the bullet pushing slope; the reduced dimension region; a positive taper region; and a tail region. In some aspects, the reduced dimension region is dimensionally reduced compared to the head region and tail region. 
     In some embodiments, a bolt can be configured for being included in a bolt action upper receiver of a bolt action upper receiver assembly. The bolt action upper receiver assembly can be configured to be coupled to a standard AR lower receiver assembly. The bolt includes a unitary body having in a longitudinal axis and a longitudinal sequence comprising: a head region having a first height from a center longitudinal axis; a negative taper region with a negative taper from the first height; a reduced dimension region having second height that is less than the first height; an end slot; an end ramp with a positive taper; and an end ridge extending from the end ramp to a bolt tail. 
     In some embodiments, a bolt can include a second longitudinal sequence with: the head region; the negative taper surface lateral of the bullet pushing slope; the reduced dimension region; a positive taper region; and a tail region. In some aspects, the reduced dimension region is dimensionally reduced compared to the head region and tail region. 
     In some embodiments, a bolt action upper receiver can be configured to be coupled with a standard AR lower receiver. The bolt action upper receiver can include a unitary receiver body having a receiver lumen. The unitary receiver body can include: a top; a proximal end having a bolt opening with the bolt of one of the embodiments located therein; and a distal end having a barrel opening. A bottom of the receiver body can include: a magazine slot open to and longitudinally aligned with a hammer slot, the hammer slot being narrower than the magazine slot; a takedown pin receiver hole at a proximal end, the takedown pin receiver hole being orthogonal with the magazine slot and hammer slot; and a pivot pin receiver hole at a distal end, the pivot pin receiver hole being orthogonal with the magazine slot and hammer slot, the pivot pin receiver hole being parallel with the takedown pin receiver hole. In some aspects, the receiver body can include a first side having: a bolt handle slot extending from the bolt opening; a bolt rest slot extending from the bolt handle slot; and an ejection port between the bolt handle slot and distal end. The receiver body can also include a second side. 
     In some embodiments, a bolt action upper receiver assembly can include: a bolt action upper receiver configured to be coupled with a standard AR lower receiver, wherein the bolt action upper receiver comprises a unitary receiver body having a receiver lumen. In some aspects, the unitary receiver body can have: a top; a proximal end having a bolt opening; a distal end having a barrel opening; a bottom, a first side and a second side. The bottom can include: a magazine slot open to and longitudinally aligned with a hammer slot, wherein the hammer slot is narrower than the magazine slot. The first side can have: a bolt handle slot extending from the bolt opening and exposing a portion of the receiver lumen; a bolt rest slot extending from the bolt handle slot; and an ejection port between the bolt handle slot and distal end. Additionally, the bolt of one of the embodiments can be slidably located in the receiver lumen. 
     In some embodiments, a bolt action rifle can include: an upper receiver; a barrel coupled to the upper receiver; the bolt of one of the embodiments in the upper receiver; and a lower receiver coupled to the upper receiver, wherein the lower receiver includes a trigger and a magazine recess. In some aspects, the bolt action rifle can include the bolt with a different second longitudinal sequence with: the head region; the negative taper surface lateral of the bullet pushing slope; the reduced dimension region; a positive taper region; and a tail region. In some aspects, the reduced dimension region is dimensionally reduced compared to the head region and tail region. In some aspects, the reduced dimension region is a cylindrical region. In some aspects, the cylindrical region includes a cylindrical surface, which includes a portion thereof that functions as the hammer pushing surface. In some aspects, the bolt includes a first body portion and second body portion that are larger dimensioned the cylindrical region, which larger dimensioned first body portion and second body portion each extends longitudinally from the cylindrical region. In some aspects, the cylindrical region is devoid of recesses or elevations between the bullet pushing slope and end slot. 
     The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       The foregoing and following information as well as other features of this disclosure will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only several embodiments in accordance with the disclosure and are, therefore, not to be considered limiting of its scope, the disclosure will be described with additional specificity and detail through use of the accompanying drawings. 
         FIG.  1    illustrates a side view of an AR rifle. 
         FIG.  2 A  illustrates a bolt action upper receiver assembly separate from a standard AR lower receiver assembly. 
         FIG.  2 B  illustrates a bolt action upper receiver assembly connected via a pivot pin to a standard AR lower receiver assembly. 
         FIG.  2 C  illustrates a bolt action upper receiver assembly connected via a pivot pin and takedown pin to a standard AR lower receiver assembly. 
         FIG.  3 A  illustrates a standard AR upper receiver assembly (semi-auto or full auto) being pivotally removed from a standard AR lower receiver assembly with the takedown pin removed therefrom. 
         FIG.  3 B  illustrates a standard AR upper receiver assembly (semi-auto or full auto) removed from a standard AR lower receiver assembly with the takedown pin and pivot pin removed therefrom. 
         FIGS.  4 A to  4 D  illustrate different views of an embodiment of a bolt action upper receiver configured to be coupled with a standard AR lower receiver assembly. 
         FIGS.  5 A- 5 C  illustrate different views of an embodiment of a barrel extension nut. 
         FIGS.  6 A- 6 D  illustrate different views of an embodiment of a bolt for a bolt action upper assembly to convert an AR rifle to a bolt action AR rifle. 
         FIGS.  7 A- 7 I  illustrate different views of an embodiment of a bolt for a bolt action upper assembly to convert an AR rifle to a bolt action AR rifle. 
         FIGS.  8 A and  8 B  illustrate an embodiment of a bolt action upper receiver assembly coupled with a standard AR lower receiver assembly. 
         FIGS.  8 C- 8 F  show the bolt action upper receiver having the bolt in sequentially rotated views. 
         FIGS.  9 A- 9 P  illustrate different views of an embodiment of a bolt for a bolt action upper assembly to convert an AR rifle to a bolt action AR rifle. 
     
    
    
     The components of the figures are arranged in accordance with at least one of the embodiments described herein, and which arrangement may be modified in accordance with the disclosure provided herein by one of ordinary skill in the art. 
     DETAILED DESCRIPTION 
     In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description, drawings, and claims are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the spirit or scope of the subject matter presented herein. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the figures, can be arranged, substituted, combined, separated, and designed in a wide variety of different configurations, all of which are explicitly contemplated herein. 
     Generally, the present invention relates to an AR rifle, such as an AR-10 and/or AR-15 or other configured and modifiable rifle as described herein. Particularly, the invention relates to a DPMS LR-308 pattern for an upper assembly and lower assembly of an AR rifle; however, it should be recognized that any appropriately configured rifle (e.g., Armalite AR-10 pattern) that can have the upper assembly separable from the lower assembly in the manner described herein may be combined with the bolt action upper assembly of the present invention. Now, with the present invention that includes a bolt action upper assembly that can be fit onto and coupled with a lower assembly (e.g., unmodified lower assembly, such as a DPMS LR-308 pattern, or Armalite AR-10 pattern), an AR rifle may be converted to a bolt action rifle by merely replacing any upper assembly or standard semi-automatic upper assembly with the bolt action upper assembly as described herein. As such, reference herein to AR rifles applies equally to the AR-10 and/or AR-15 or other similar rifles. One of skill in the art can use the teachings related to the AR-10 bolt action upper assembly provided herein in order to prepare an AR-15 bolt action upper assembly or any other AR rifle having the same. While the application teaches the DPMS LR-308 pattern, the teachings are also for an Armalite AR-10 pattern. 
     As used herein, the “AR” is intended to mean a rifle of the type of AR platform rifles (e.g., ArmaLite rifle) that are commonly known, which are “assault rifle” type and may be “automatic rifle” type or “semi-automatic rifle type. Otherwise, the AR is as defined herein. Also, it should be understood that the AR may be of any manufacturer that makes an AR rifle as known and understood by one of ordinary skill in the art. It is well known that an AR rifle is a specific platform and type of rifle. 
     By way of example and background, a standard semi-automatic AR rifle is shown in  FIG.  1   . In some instances, features of the standard semi-automatic AR rifle can be included in the bolt action upper assembly, such as the barrel, barrel nut, and other aspects of mounting the barrel to the upper assembly. Also, the firing pin of a standard semi-automatic upper assembly may be utilized in the bolt action upper assembly. The present invention provides a bolt action upper assembly that mounts to a standard AR rifle lower assembly as described herein. In fact, the bolt action upper assembly is configured to be self-contained and attachable to the lower assembly by using the takedown pin (e.g., rear pin) and pivot pin (e.g., front pin). For example, removing the takedown pin and pivot pin from a standard semi-automatic AR rifle allows the standard semi-automatic upper assembly to be removed from the standard lower assembly, and then the bolt action upper assembly can be mounted onto the standard lower assembly with the takedown pin and pivot pin replaced in order to arrive at the fully functional bolt action AR rifle. 
       FIG.  1    shows an assembled AR-10.  FIG.  1    shows the semi-automatic upper assembly  1  mounted to the standard lower assembly  101 A via the takedown pin  123  and pivot pin  120  being received through the proper holes in the upper assembly  1 A and lower assembly  101 A, such as described herein. 
     A standard automatic or semi-automatic AR-10 upper assembly  1 A often includes an upper receiver, charging handle assembly, bolt carrier assembly, barrel tube, slip ring retaining ring, slip ring spring assembly, barrel nut, slip ring, gas tube, handguard, handguard cap, picatinny gas block, picatinny housing clamp screw, gas tube pin, spiral pin, front sling swivel, crush washer, and flash suppressor. An upper pivot pin receiver hole  20  (e.g., for receiving the pivot pin  120 ) and an upper takedown pin receiver hole  22  (e.g., for receiving the takedown pin  123 ) are shown to receive pins (e.g., pivot pin  120  and takedown pin  123 ) from the lower assembly  101 A in order to form the full AR-10. Due to the pivot pin  120  and takedown pin  123  being installed in the upper pivot pin receiver hole  20  and upper takedown pin receiver hole  22 , respectively, the upper pivot pin receiver hole  20  and upper takedown pin receiver hole  22  are not clearly seen; however, they are shown in other figures provided herein. 
     It should be noted that the barrel tube  4 , slip ring retaining ring  5 , slip ring spring assembly  6 , barrel nut  7 , and slip ring  8 , can, in some embodiments, be used to mount the barrel to the inventive bolt action upper assembly as described herein; however, some embodiments may omit these components. The hand guard  10  may also be used with the bolt action upper assembly. In other embodiments, an AR free float fore end is included in the inventive bolt action upper assembly as described herein. In some embodiments, a fore end having a gas block is excluded from the present invention. 
     An assembled bolt action AR having the bolt action upper assembly mounted to a lower assembly  101 A may be provided in an embodiment. The lower assembly  101 A can include the lower receiver  101 , buttstock assembly  102 , receiver extension tube, operating spring  104  ( FIG.  3 B ), buffer  105 , buttstock spacer, buttstock screw, buffer detent, pistol grip  110 , pistol grip screw, pistol grip washer, bolt stop, bolt stop pin, bolt stop plunger, bolt stop spring, magazine catch, magazine catch button, magazine catch spring, pivot pin  120 , detent pin, detent spring, takedown pin  123 , safety selector, safety spring, safety detent, trigger pin, two stage tactical hammer, D-ring, hammer torsion spring, trigger spring, two stage trigger  132 , coiled spring pin, two stage disconnector, disconnector spring, trigger guard assembly  136 , and trigger guard pin. Pivot pin receiver hole  138  is shown to receive the pivot pin  120  (e.g., difficult to see due to the pivot pin  120  being therein) and takedown pin receiver hole  139  is shown to receive the takedown pin  123  (e.g., difficult to see due to the takedown pin  123  being therein). The entirety of the lower receiver  101  and/or lower assembly  101 A may be used for the bolt action AR rifle described herein, where the entirety of the lower receiver assembly  101 A may be mounted to the bolt action upper receiver assembly. 
     To mount the upper assembly  1 A with the lower assembly  101 A, the upper pivot pin receiver hole  20  is aligned with the lower pivot pin receiver hole  138  with the pivot pin  120  being received therethrough, and the upper takedown pin receiver hole  22  is aligned with the lower takedown pin receiver hole  139  with the takedown pin  123  received therethrough. Pulling out the takedown pin  123  and pivot pin  120  allows disassembly, and replacement of the takedown pin  123  and pivot pin  120  allows assembly. 
     The AR-10 can include a bolt carrier assembly having the firing pin retaining pin, firing pin, firing pin spring, cam pin, bold carrier, key screws, bold carrier key, and bolt assembly as separate parts. Here, the firing pin, and firing pin spring can be used with the bolt of the bolt action upper assembly. 
     The AR-10 can include a bolt assembly having the gas ring, bolt, extractor spring insert, extractor spring, o-ring, extractor, extractor pin, ejector pin, ejector spring, and ejector. Here, the extractor spring insert, extractor spring, and extractor can be used in the bolt action bolt assembly described herein. Also, the ejector spring and ejector may also be used for brass ejection with the bolt action bolt assembly. 
       FIGS.  2 A- 2 C  shows an AR-10 bolt action (AR-10 BA) upper assembly  300  separate from the lower assembly  101 A and then the coupling of the upper assembly  300  to the lower assembly  101 A in order to form the bolt action AR rifle  200  in  FIG.  2 C .  FIG.  2 C  shows the lower assembly  101 A with the pivot pin  120  and takedown pin  123  in the receiver holes to fasten the bolt action (BA) upper assembly  300  to the lower assembly  101 A, which is the assembled bolt action AR rifle  200 .  FIG.  2 A  shows the upper assembly  300  separate from the lower assembly  101 A. It is noted that this lower assembly  101 A is the standard lower assembly for the semi-automatic AR rifle.  FIG.  2 B  shows the takedown pin  123  being removed from the upper takedown pin receiver hole  22  so that the back of the BA upper assembly  300  can pivot on the pivot pin  120  in the upper pivot pin receiver hole  20 . It is noted that the upper takedown pin receiver hole  22  is in a takedown receiver body, and the upper pivot pin receiver hole  20  is in a takedown pin receiver body. As shown, the takedown pin  123  and pivot pin  120  do not need to be pulled all the way out of the takedown pin receiver hole  139  and pivot pin receiver hole  138 , but only from the upper takedown pin receiver hole  22  and upper pivot pin receiver hole  20 . Performing the steps from  FIG.  2 C to  2 A  disassembles the AR-10 BA, and performing the steps from  FIG.  2 A to  2 C  assembles the AR-10 BA. Also, it can be seen that the takedown pin receiver hole  139  is actually two different holes, one on each side of the lower assembly  101 A, and thereby the takedown pin  123  only needs to be withdrawn from one and from the upper takedown pin receiver hole  22 . Also, it can be seen that the pivot pin receiver hole  138  is actually two different holes, one on each side of the lower assembly  101 A, and thereby the pivot pin  120  only needs to be withdrawn from one and from the upper pivot pin receiver hole  20 . 
     In one aspect, the subject matter described herein is related to a DPMS LR-308 pattern BA upper assembly, DPMS LR-308 pattern SA upper assembly, DPMS LR-308 lower assembly, and DPMS AR-10 BA or DPMS AR-10 SA. The subject matter may also relate to AR-15s, SA upper assemblies thereof, BA upper assemblies thereof, and lower assemblies thereof, which may also be DPMS LR-308 patterned. Also, it may be an Armalite AR-10 pattern. 
       FIG.  1    shows an AR-10 semi-automatic (AR-10 SA) with the pivot pin  120  and takedown pin  123  in the receiver holes to fasten the semi-automatic (SA) upper assembly  1 A to the lower assembly  101 A.  FIG.  3 A  shows the takedown pin  123  removed from the upper assembly  1 A so that the SA upper assembly  1 A pivots on the pivot pin  120 .  FIG.  3 B  shows the pivot pin  120  removed so that the SA upper assembly (not shown) is detached from the lower assembly  101 A. Optionally, the operating spring  104  can be removed or retained therein when the BA upper assembly  300  is mounted to the lower assembly. Performing the steps from  FIG.  1 A  to  FIG.  3 A  to  FIG.  3 B  disassembles the AR-10 SA, and performing the steps from  FIG.  3 B  to  FIG.  3 A  to  FIG.  1    assembles the AR-10 SA. 
     Accordingly, the present invention can include a BA upper assembly that mounts to a lower assembly to form an AR-10 BA rifle. The present invention can also include the AR-10 BA rifle having the BA upper assembly mounted to the lower assembly. The present invention can also include a kit including the lower assembly with the SA upper assembly and BA upper assembly. The present invention may also include a method of converting an AR-10 SA rifle into an AR-10 BA rifle. The present invention may also include a method of attaching a BA upper assembly to a lower assembly to form the AR-10 BA rifle. The present invention may also include a method of disassembling an AR-10 BA rifle into a BA upper assembly and a lower assembly. Other assemblies, guns, kits, systems, and methods of making/assembling or methods of disassembling are also included. The methods may include assembling and/or disassembling the BA upper assembly. The individual components of the BA upper assembly may also be embodiments of the invention. 
       FIGS.  4 A- 4 D  show different views of the upper receiver  402  of a BA upper assembly  300 , which is configured for bolt action firing.  FIG.  4 B  shows a perspective view and  FIG.  4 C  shows a bottom view of the upper receiver  402 . The bottom view of  FIG.  4 C  shows that the same magazines of an AR-10 SA may fit into the BA upper assembly  300  and thereby the AR-10 BA.  FIG.  4 D  shows the other side of the upper receiver  402 .  FIGS.  6 A- 6 D  show the barrel extension nut  420 .  FIGS.  6 A- 6 D  show different perspectives of the bolt  450 . 
     The receiver  402  includes a threaded receiver  404  for receiving the barrel, which threaded receiver  404  is shown without threading. A barrel extension nut  420  ( FIG.  5 A ) is adapted to be received onto the threaded receiver  404 . A threaded relief  408  is behind the threaded receiver  404 . The threaded receiver  404  includes a dowel pin receiver  406  that is configured to receive a dowel pin, where the dowel pin keys into the dowel pin receiver  406 . The threaded receiver  404  is threaded the same as an AR upper receiver. The barrel threads into the barrel extension nut  420 , and then the barrel extension nut  420  slides in the receiver  402  into a tight fitting so that the dowel pin hole  422  of the barrel extension nut  420  aligns with the dowel pin receiver  406 , and then the dowel pin is received into the dowel pin hole  422  and dowel pin receiver  406 . The barrel extension nut  420  ( FIGS.  5 A- 5 C ) then goes over the barrel  4 A and tightens to the threaded receiver  404 , where the barrel extension nut  420  is on the outside and locks down the barrel to the receiver  402 . As such, the barrel  4   a  may be attached to the upper assembly  300  by threading it into the barrel extension nut  420  that is then mounted to the receiver  402 . A barrel extension nut  420  can be used to attach the barrel into the receiver  402 . 
       FIG.  4 A  shows the receiver  402  having the picatinny rail  410  for scope adjustment, which has grooves for receiving a sight or scope. For example, the picatinny rail  410  can be configured with the 20 MOA slope, which allows for more accurate long distance shooting. The picatinny rail  410  also allows for better usage of internal adjustment mechanisms of a scope that can be attached thereto, which is beneficial for long distance shooting. Here, the picatinny rail  410  is integrated, but it could be a separate part. The reason why it is integrated is that the bolt action allows for longer range shooting with accuracy, which can be facilitated with the 20 minute slope of the rail  410 . It also allows for more rigidity that enhances shooting accuracy. 
     The receiver  402  includes the upper pivot pin receiver hole  20  for receiving the pivot pin  120  and the takedown pin receiver hole  22  for receiving the takedown pin  123  as shown in other figures. 
     The receiver  402  is shown to include the bolt handle slot  412  for receiving the bolt handle  414  ( FIG.  2 B ), which bolt handle  414  can slide there along while actuating the bolt action. The distal end of the bolt handle slot  412  includes an extractor ramp  416  that is configured for facilitating extraction of the brass by actuation of the bolt handle  414  by being guided thereby when being removed from the bolt rest  418 . The other end of the bolt handle slot  412  is open as shown at  412   a . The brass is then ejected through the ejection port  424 . When the bolt handle  414  is in the bolt rest  418  and pulled down into it and seated, then the rifle can fire. If the bolt handle  414  is not all the way seated into bolt rest  418 , the rifle will not fire because the bolt  450  ( FIG.  6 A ) is designed to inhibit the hammer from properly actuating unless the bolt handle  414  is fully seated in the bolt rest  418 , which is described in more detail herein. 
     The extractor ramp  416  (in dashed circle) is angled from the bolt rest  418  toward the bolt handle slot  412  to facilitate extraction of the brass from the ejection port  424 . As can be seen, the bolt rest  418  and bolt handle slot  412  are at roughly 90 degrees, however, the distal or forward edge (e.g., opposite of  412   a ) has the extractor ramp  416  at an angle between the bolt rest  418  and bolt handle slot  412  instead of a 90 degree angle. This extractor ramp  416  is provided to push the bolt handle  414  in an amount and direction to initiate extraction of the brass from the chamber. The extractor ramp  416  also facilitates easier proximal or backward pulling of the bolt handle  414 . In some instances if heating occurs, the brass may get stuck in the chamber, and upon manipulating the bolt handle  414  from the bolt rest  418  into the extractor ramp  416  can cause the bolt handle  414  to be pushed proximal or backwards toward the shooter in order to enhance brass extraction. 
     Also shown in  FIGS.  4 A- 4 D  are the top  440 , bottom  441 , distal end  442  having the barrel opening  443 , proximal end  444  having the bolt opening  445 , the first side  446  having the first side upper surface  447   a , first side lower surface  447   b , and second side  448  (e.g., having a logo or other indicia) having the second side upper surface  449   a  (e.g., containing the logo or other indicia as shown) and second side lower surface  449   b.    
       FIG.  4 B  shows a perspective view of some of the features of the receiver  402 . 
       FIG.  4 C  shows the bottom of the receiver  402 , and shows the magazine slot  426  configured for receiving the magazine, which within includes the detent ball  428 . The magazine slot  426  opens into the hammer slot  427  (e g, hammer slot  427  narrower, proximal, and fluid with the magazine slot  426 ) configured for allowing the hammer to actuate therethrough. The detent ball  428  (in a detent recess) matches a recess  432  in the bolt  450  so that the bolt  450  stays closed and does not rattle open or rattle around during use. There is a spring in the detent recess that resiliently pushes the detent ball  428  outward so that the detent ball  428  can be pushed into the detent recess. 
     Near the upper takedown pin receiver hole  22 , there is a threaded hole  430 . The threaded hole  430  is adapted to receive a bolt therein so that the receiver  402  can be bolted to the lower assembly, where a fastener (e.g., threaded fastener, such as a screw etc.) can be passed through the lower assembly into the receiver  402  and threaded into the threaded hole  430 . This can increase rigidity of the mounted receiver  402  into the lower assembly and increase accuracy of firing. Such a coupling with a fastener is optional, and if used is removed along with the takedown pin  123  and pivot pin  120 . 
       FIG.  4 D  shows the other side of the receiver  402 , which shows the magazine release receiver recess  427 , which receives the magazine release button. It should be noted that the receiver  402  is contoured to fit into the lower assembly, such as the back being rounded for a tight fitting. 
       FIGS.  5 A- 5 C  show the barrel extension nut  420  having the dowel pin hole  422 . Also, the barrel extension nut  420  includes a shell guide ramp  421  on nut lugs  421   a  that are sloped to guide shells. The barrel extension nut  420  also includes reliefs  423  between the nut lugs  421   a  for receiving the bolt head lugs  460  of the bolt tip  458 . 
     During operation, the bolt tip  458  passes through relief  423 , and then as the bolt  450  is rotated to be closed and to be in a firing position, the bolt tip  458  spins in the relief  423  behind the lugs  460  on the barrel extension nut  420 . This allows proper engagement when manually engaging the bolt into a firing position. 
       FIG.  6 A  shows the bolt  450 , which includes the firing pin  470  therein ( FIG.  6 C ). The bolt  450  includes the bolt handle hole  452  for coupling with the bolt handle  414 , and whereby the bolt handle hole  452  is aligned with the bolt handle slot  412  when the bolt  450  is in the receiver  402 . The bolt  450  may optionally include a roll pin hole  454  for holding the firing pin; however, there are other options for retaining the firing pin. The bolt  450  also includes an extractor slot  456  in the bolt tip  458  having bolt head lugs  460  (e.g.,  3  of them). One of the bolt head lugs  460  includes the extractor slot  456 , which can include the extractor components to facilitate extraction of the brass from the chamber. The bolt head lugs  460  fit into the relief  423  of the barrel extension nut  420 . The bolt tip  458  has a bolt head recess  462  that also has holes, such as the spring plunger hole  464  that houses a springed plunger (not shown) to facilitate ejection of brass. 
     When included, the roll pin hole  454  receives a roll pin (not shown), which holds the firing pin in. The firing pin is free floating. The firing pin can be any standard AR-10 firing pin. In one option, the firing pin can be a DPMS LR-308 AR firing pin, such as AR-10 (e.g., Armalite AR-10) or AR-15. 
       FIG.  6 B  shows a bottom side  450   a  of the bolt  450  with the bolt tip  458 , bolt neck  470  adjacent to the bolt tip  458 , and bolt body  472 . Near the bolt neck  470 , the bolt body  472  includes a bullet pushing ridge  474  that has a bullet pushing slope  476  opposite of the bolt tip  458  across the bolt neck  470 . The bullet pushing ridge  474  may extend further down the bolt body  472  as needed or desired (illustrated in another embodiment) and function for hammer pushing. On the side of the bolt body  472  (e.g., orthogonal with the bottom side) is a magazine recess  478  that has a surface that when the bolt  450  is closed, the magazine recess  478  allows operation of the magazine. 
     Opposite of the bolt tip  458  is a bolt end  480  that has a firing pin recess  482  for retaining the firing pin therein. The firing pin recess at the bolt end  482  is next to an end ridge  484  with an end ramp  486 . The end ridge  484  and end ramp  486  allow for proper operation of the rifle by setting the hammer in a locked position. The end ridge  484  keeps the hammer set in the locked position while the bolt  450  is in the open position all of the way forward. The end ramp  486  is what pushes the hammer back down once it has come off of the hammer ridge  490  while pushing the hammer forward after firing the rifle so that the hammer can again rest on the end ridge  484  before closing the bolt  450 . 
     There is an end slot  488  at the firing pin recess  482  next to the end ramp  486 , where the end slot  488  has a dimension D from the end ridge  484  and/or end ramp  486  and a dimension D 1  from the end  482 . The dimension D is configured for hammer clearance in the end slot  488 . The dimension D 1  is from the end and allows for operation, with the end ridge  484  extending from the body  472  to make the end slot  488  shaped as shown. The end ridge  484  can keep the gun from shooting by keeping the hammer set in the locked position, but once the hammer is in the end slot  488 , the hammer can release. Thus, when the bolt  450  is open, the rifle can&#39;t shoot, but when the bolt  450  is closed the hammer is in the end slot  488  and the rifle is able to fire. 
     The AR has a swinging hammer that is received into the end slot  488 , and which strikes the firing pin within the bolt  450 . When the bolt  450  is drawn back, it pushes the hammer back, and the hammer pushing ridge (e.g., end ridge  484 ) sets the hammer. 
       FIGS.  6 C and  6 D  show alternate views showing components of the bolt  450 . It is noted that the bolt  450  is a unitary member, which is advantageous for the simple method of conversion from semi-automatic to bolt action. 
       FIGS.  7 A- 7 G  show different views of an alternative bolt  550  that is adapted for enhanced security and safety. Different views are from rotation of the bolt  550  to show all of the features thereof. This bolt  550  does not allow for the rifle to fire unless the bolt handle  414  is seated down into the bolt rest  418 . A lot of the features of the bolt  450  are included in the bolt  550 , which include the same element numbers. 
       FIGS.  7 A- 7 I  show different views of the bolt  550 , which includes the bolt neck  470  therein. The bolt  550  includes the bolt handle hole  452  for coupling with the bolt handle  414 , and whereby the bolt handle hole  452  is aligned with the bolt handle slot  412  when the bolt  550  is in the receiver  402 . The bolt  450  also includes an extractor slot  456  in the bolt tip  458  having bolt head lugs  460  (e.g.,  3  of them). One of the bolt head lugs  460  includes the extractor slot  456 , which can include the extractor components to facilitate extraction of the brass from the chamber. The bolt head lugs  460  fit into the relief  423  of the barrel extension nut  420 . It should be noted that the bolt tip  458  includes the bolt head lugs  460  separated by bolt head reliefs  461 , and the barrel extension nut  420  includes the nut lugs  421   a  separated by the nut relief  423 . When actuated, the bolt head lugs  460  pass through the nut reliefs  423  and the nut lugs  421   a  pass through the bolt head relief  461 , and then when rotated the bolt head lugs  460  are aligned with the nut lugs  421   a  so that the bolt head relief  461  is aligned with the nut reliefs  423 . 
     The bolt  550  is shown with the bolt tip  458 , bolt neck  470  adjacent to the bolt tip  458 , and bolt body  472 . Near the bolt neck  470 , the bolt body  472  includes a bullet pushing ridge  474  that has a bullet pushing slope  476  opposite of the bolt tip  458 . The bullet pushing ridge  474  may extend further down the bolt body  472  as needed or desired and function for hammer pushing. On the side of the bolt body  472  is a magazine recess  478  that has a surface that when the bolt  550  is closed, the magazine recess  478  allows operation of the magazine. 
     Opposite of the bolt tip  458  is a bolt end  480  that has firing pin recess  482  for retaining the firing pin therein. The firing pin recess  482  is next to an end ridge  484  with an end ramp  486 . 
     Also shown are a first body portion  473  and second body portion  475  at the ends of the magazine recess  478 . The first body portion  473  and second body portion  475  are portions of the cylindrical portion  477 . 
     From the bullet pushing slot  476  is a hammer pushing ridge  490 , which is adapted to push the hammer down and keeps the gun from firing until the bolt  550  is locked. The hammer pushing ridge  490  can have the same height from the bolt body  472  as the end ridge  484 . There is an end slot  488  at the firing pin recess  482 , where the end slot  488  has a dimension D from the end ridge  484  and/or end ramp  486  to the hammer pushing ridge  490 . The dimension D is configured for hammer clearance in the end slot  488 . The hammer pushing ridge  490  can keep the gun from shooting by preventing the hammer from setting, but once the hammer is in the end slot  488 , the hammer can set. Thus, when the bolt  550  is open, the gun can&#39;t shoot, but when the bolt  550  is closed the hammer is in the end slot  488  and the gun is able to fire. 
     The AR has a swinging hammer that is received into the end slot  488 , and which strikes the firing pin within the bolt  550 . When the bolt  550  is drawn back, it pushes the hammer back, and the hammer pushing ridge  484  sets the hammer. 
     The hammer pushing ridge  490  is dimensioned to keep the hammer cocked and the hammer set so that it cannot shoot until the bolt  550  is fully set with the bolt handle  414  in the bolt rest  418 . The hammer pushing ridge  490  is shaped to make sure the hammer is held to that certain point where the gun will not fire even after the bolt is closed. Because if the hammer is not held properly, an operator can pull the trigger and as soon as the bolt is closed, the hammer can go off. Now with the hammer ridge  490  abutting and extending from the bullet pushing ridge  474  or slope  476  all the way to the end slot, the upper receiver  402  is safe and not allowed to fire until the trigger is pulled. This is surprising and unexpected that such a hammer pushing ridge  490  or combination of the hammer pushing ridge  490  with the bullet pushing ridge  474  or slope  476  extending to the end slot  488  can make the bolt action upper assembly  300  safe to mount to a lower assembly to form the AR-10 BA rifle. As such, the end slot  488  is configured for hammer clearance so the hammer clears when the bolt  550  is in firing position. 
     The dimension D is important for hammer clearance. The dimension D can be about 1″, or +/−1%, 2%, 5%, or 10% for an AR-10; however, an AR-15 can have different values for the dimension D. When the bolt  550  is closed, it is in a position so that the hammer can swing the full length for firing the rifle. But when the bolt  550  is opened, the hammer pushing ridge  490  holds the hammer so that it cannot strike the firing pin so that the rifle cannot fire. The hammer clearance D is dimensioned so that once the rifle has fired, you can still draw the bolt  550  back to get the hammer to cock again. The hammer clearance for dimension D allows the hammer to be able to sit on the hammer pushing ridge  490  as you open your bolt  550  and draw it back. When the hammer is on the hammer pushing ridge  490 , the gun cannot go off. The only way the hammer can go forward is if the bolt  550  is closed. 
     The end ramp  486  and end ridge  484  make sure that when the bolt  550  is not fully seated, the gun will not fire. While the hammer may be pulled forward, it is at an angle that does not hit the firing pin. When pushing the bolt  550  forward you can get to where the hammer is between the hammer pushing ridge  490  and the end ramp  486 , you can pull the trigger and the hammer will go off, but it can&#39;t hit the firing pin because it&#39;s on the wrong angle. So the gun still can&#39;t go off. Even if you close the bolt  550  all the way with the hammer forward, the gun is not going to go off. The bolt  550  has to be rotated and seated so that the bolt handle is seated in the bolt rest in order for the gun to fire. As such, the bolt  550  provides safety mechanisms so that the gun does not fire until the bolt is set with the bolt handle in the bolt rest. 
       FIGS.  8 A- 8 F  show portions of the bolt action upper assembly  800  mounted to the standard lower assembly  101 A, with and without the barrel guard. These figures show the arrangement of the elements as described herein. From  FIG.  8 A  to  FIG.  8 F , various components are removed so that the arrangement of the outer components can be viewed relative to the inner components. For example,  8 C shows the relationship of the hammer assembly  802  relative to the upper assembly  800  with respect to the receiver  402 .  FIG.  8 D  shows a rotation from the view of  FIG.  8 C .  FIG.  8 E  shows a rotation from the view of  8 D.  FIG.  8 F  shows the relationship of the hammer assembly  802  with the bolt  550 . 
       FIGS.  9 A- 9 P  show different views of another alternative bolt  950  that is adapted for enhanced security and safety and easier machining and manufacturing. The bolt  950  is designed for improve manufacturability and reproducibility by simplifying the features and retaining the improvements that still provide for use described herein Different views are from rotation of the bolt  950  or portions thereof to show all of the features thereof. This bolt  950  does not allow for the rifle to fire unless the bolt handle  414  is seated down into the bolt rest  418 . A lot of the features of the bolt  450  and bolt  550  are included in the bolt  950 , which include the same element numbers. 
       FIGS.  9 A- 9 P  show different views of the bolt  950 , which includes the bolt neck  470  therein. The bolt  950  includes the bolt handle hole  452  for coupling with the bolt handle  414 , and whereby the bolt handle hole  452  is aligned with the bolt handle slot  412  when the bolt  950  is in the receiver  402 . The bolt  950  also includes an extractor slot  456  in the bolt tip  458  having bolt head lugs  460  (e.g.,  3  of them). One of the bolt head lugs  460  includes the extractor slot  456 , which can include the extractor components to facilitate extraction of the brass from the chamber. The bolt head lugs  460  fit into the relief  423  of the barrel extension nut  420 . It should be noted that the bolt tip  458  includes the bolt head lugs  460  separated by bolt head reliefs  461 , and the barrel extension nut  420  includes the nut lugs  421   a  separated by the nut relief  423 . When actuated, the bolt head lugs  460  pass through the nut reliefs  423  and the nut lugs  421   a  pass through the bolt head relief  461 , and then when rotated the bolt head lugs  460  are aligned with the nut lugs  421   a  so that the bolt head relief  461  is aligned with the nut reliefs  423 . 
     The bolt  950  is shown with the bolt tip  458 , bolt neck  470  adjacent to the bolt tip  458 , and bolt body  972  (e.g., cylindrical). Near the bolt neck  470 , the bolt body  972  includes a bullet pushing ridge  474  that has a bullet pushing slope  476  opposite of the bolt tip  458 . The bullet pushing ridge  474  may extend further down the bolt body  972  as needed or desired and function for hammer pushing. On the side of the bolt body  972  is a cylindrical region  978  that has a cylindrical surface that when the bolt  950  is closed, the cylindrical region  978  allows operation of the magazine. 
     The cylindrical region  978  can be completely smooth around the circumference without recesses or elevations; however, some embodiments may include machined recesses or elevations in the cylindrical region. The cylindrical region  978  can be a uniform diameter from the lug end to the back end. 
     Additionally, the cylindrical region allows for the bolt  950  to be divided up onto distinct regions, such as the lug region, neck region, head region, negative taper region, cylindrical region, positive taper region, and tail region. The features of the bolt  950  included in these regions are described herein. 
     The circumferential region having the lugs  460  is considered to be the lug region, which has bounds by the longitudinal ends of the lugs  460 . 
     The circumferential neck region includes the neck  470  (e.g., radially reduced compared to lug region or having smaller diameter and smaller circumference) and has a first boundary defined by the end of the lugs  460 , and a second boundary defined by the radially expanded and larger diameter and larger circumferential head region. 
     The circumferential head region includes the bullet pushing ridge  474 . The head region is mostly cylindrical with grooves cut out on either side of the bullet pushing ridge  474 . This divides the circumferential head region into a bullet region having the bullet pushing ridge  474  and a support region that is most of the head region, which two regions are separated by the longitudinal grooves therebetween. 
     The circumferential negative taper region includes bullet pushing slope  476  and extends from the end of the bullet pushing ridge  474  to the end of the bullet pushing slope  476 . The negative taper region is divided into two regions separated by the same longitudinal grooves in the head region. The bullet pushing slope  476  defines the bullet region, and the majority of the negative taper region includes a surface that tapers from the head region to the cylindrical region. 
     The cylindrical region  978  is substantially a smooth cylinder, but may have some features machined therein. The cylindrical region  978  has a reduced diameter and reduced circumference compared to the head region, which difference is defined by the height of the taper of the negative tapered region. In some embodiments, the cylindrical region  978  is devoid of any recesses or ridges. In some aspects, the cylindrical region  978  can be devoid of any recess or other feature that provides a unique space for avoiding the magazine when installed. The cylindrical region  978  allows for the magazine by having a uniformly reduced dimension that provides the diameter of the cylinder. The narrowed diameter and narrowed circumference provide clearance for the magazine without need for an additional recess. The uniform diameter cylindrical region  978  without any recesses or elevations surprising and unexpectedly improves manufacturing by significant simplification, and still accommodates the magazine with sufficient strength for long lasting operability of the bolt in the firearm. 
     The positive taper region has a positive taper profile starting from the cylindrical region  978  and extending to the larger diameter and larger circumference tail region. The positive taper region includes the taper surface mostly around the circumference except for a flat or longitudinal surface that is substantially planar and continuous with a portion of the cylindrical region  978 , as discussed in more detail herein. 
     The tail region extends from the positive taper region to the end of the bolt  955 . The tail region includes the slots and features described herein at this tail end of the bolt. The tail region mostly includes a larger diameter compared to the cylindrical region, except for planar surfaces machined therein. In some instances, the tail region is larger in diameter and circumference than the cylindrical region except for the slot and planar surface formed into the tail region. The larger diameter extends mostly around the tail region to provide support to the lumen of the receiver in which the bolt  950  operably slides within. The cross-sectional dimension (e.g., diameter) of the head region and the tail region can be larger than the cylindrical region  978 , except for the longitudinal grooves in the head region and the planar surface and slot in the tail region. If perfect circles, the cross-sectional profile of the head region and tail region have a greater diameter or cross-sectional dimension than the cylindrical region. 
     Opposite of the bolt tip  458  (e.g., distal end, first end, or head end) is a bolt end  480  (e.g., proximal, second or tail) that has firing pin recess  482  (e.g., slot, hollowed for retaining the firing pin therein). The firing pin recess  482  is next to an end ridge  484  with an end ramp  486 . 
     Also shown are a first body portion  473  and second body portion  475  at the ends of the magazine recess  478 , with the cylinder region  978  therebetween. The first body portion  473  and second body portion  475  are portions of the larger cylindrical portions longitudinal of the narrowed or reduced dimensioned cylindrical region  978 . The first body portion  473  includes at least the head region and the second body portion includes at least the tail region. 
     From the bullet pushing slope  476  is a hammer pushing surface  990  of the surface of the cylindrical region  978 , which is adapted to push the hammer down and keeps the gun from firing until the bolt  950  is locked. The hammer pushing surface  990  can have the same height from the bolt body  972  as the end ridge  484 . There is an end slot  488  at the firing pin recess  482 , where the end slot  488  has a dimension D from the end ridge  484  and/or end ramp  486  to the hammer pushing surface  990 . The dimension D is configured for hammer clearance in the end slot  488 . The hammer pushing surface  990  can keep the gun from shooting by preventing the hammer from setting, but once the hammer is in the end slot  488 , the hammer can set. Thus, when the bolt  950  is open, the gun can&#39;t shoot, but when the bolt  950  is closed the hammer is in the end slot  488  and the gun is able to fire. 
     The AR has a swinging hammer that is received into the end slot  488 , and which strikes the firing pin within the bolt  950  (e.g., see  FIGS.  9 H- 9 K and  9 N ). When the bolt  950  is drawn back, it pushes the hammer back, and the hammer pushing ridge  484  sets the hammer. 
     The hammer pushing surface  990  is dimensioned to keep the hammer cocked and the hammer set so that it cannot shoot until the bolt  950  is fully set with the bolt handle  414  in the bolt rest  418 . The hammer pushing surface  990  is dimensioned at a set value from the center axis (e.g., longitudinal axis) to make sure the hammer is held to that certain point where the gun will not fire even after the bolt is closed. Because if the hammer is not held properly, an operator can pull the trigger and as soon as the bolt is closed, the hammer can go off. Now with the hammer surface  990  abutting and extending from the bullet pushing ridge  474  or slope  476  all the way to the end slot  488 , the upper receiver  402  is safe and not allowed to fire until the trigger is pulled. This is surprising and unexpected that such a hammer pushing surface  990  (e.g., hammer pushing dimension of cylinder or hammer pushing radius from central axis) or combination of the hammer pushing surface  990  with the bullet pushing ridge  474  or slope  476  extending to the end slot  488  can make the bolt action upper assembly  300  safe to mount to a lower assembly to form the AR-10 BA rifle. As such, the end slot  488  is configured for hammer clearance so the hammer clears when the bolt  550  is in firing position. 
     Additionally, the tail end includes a planar tail surface  991  that is continuous with the bullet pushing surface  990  of the cylindrical region  978 . The planar tail surface  991  is continuous with the end ridge  484 , such that the planar tail surface  991  and end ridge have a common planar surface that is continuous with the round surface of the cylindrical region  978 , which can be seen in  FIGS.  9 B,  9 C, and  9 E . 
     The dimension D is important for hammer clearance. The dimension D can be about 1″, or +/−1%, 2%, 5%, or 10% for an AR-10; however, an AR-15 can have different values for the dimension D. When the bolt  950  is closed, it is in a position so that the hammer can swing the full length for firing the rifle. But when the bolt  950  is opened, the hammer pushing surface  990  holds the hammer so that it cannot strike the firing pin so that the rifle cannot fire. The hammer clearance D is dimensioned so that once the rifle has fired, you can still draw the bolt  950  back to get the hammer to cock again. The hammer clearance for dimension D allows the hammer to be able to sit on the hammer pushing surface  990  as you open your bolt  950  and draw it back. When the hammer is on the hammer pushing surface  990 , the gun cannot go off. The only way the hammer can go forward is if the bolt  950  is closed. 
     The end ramp  486  and end ridge  484  make sure that when the bolt  950  is not fully seated, the gun will not fire. While the hammer may be pulled forward, it is at an angle that does not hit the firing pin. When pushing the bolt  950  forward you can get to where the hammer is between the hammer pushing surface  990  and the end ramp  486 , you can pull the trigger and the hammer will go off, but it can&#39;t hit the firing pin because it&#39;s on the wrong angle. So the gun still can&#39;t go off. Even if you close the bolt  950  all the way with the hammer forward, the gun is not going to go off. The bolt  950  has to be rotated and seated so that the bolt handle is seated in the bolt rest in order for the gun to fire. As such, the bolt  950  provides safety mechanisms so that the gun does not fire until the bolt  950  is set with the bolt handle in the bolt rest. 
     The head is also shown to include the head holes  954   a  and  954   b . The head hole  954   a  is for a vent (e.g., vent hole) into the firing pin hole, which is helpful in case of a primer failure to vent the pressure from building up from the case. This prevents the firing pin from being blown out the back of the bolt. The head recess  954   b  is a recess or divot for receiving a detent ball to go in to keep the bolt closed when there is no round in the chamber. 
       FIG.  9 G  shows the tip of the bolt  950 . 
       FIG.  9 H  shows the tail of the bolt  950 . 
       FIG.  9 I-K  show different perspective views of the tail of the bolt  950 . 
       FIG.  9 L  shows a rotated side view of the tail of the bolt  950 . 
       FIG.  9 M  shows a rotated perspective view of the tail of the bolt  950 . 
       FIG.  9 N  shows a cross-sectional view of the bolt  950 , which shows the internal lumen having the tail lumen, narrowed lumen, cylindrical lumen, and head lumen. 
       FIG.  9 O  shows a bisected view of the bolt  950  which is bisected at the cylindrical region  978 . 
       FIG.  9 P  shows another bisected view of the bolt  950  which is bisected at the pushing ramp  476 . 
       FIGS.  9 I- 9 L  show that the tail end has the firing pin recess  482  and the end slot  488  at the firing pin recess  482  next to the end ramp  486 , where the end slot  488  has a dimension D from the end ridge  484  and/or end ramp  486  and a dimension D 1  from the end  482 . The firing pin recess  484  is recessed into the tail end  480  of the bolt  950 . The firing pin recess  484  also opens to the end slot  488 . This forms an L shaped planar tail surface  991  and cooperative L shaped opening from the firing pin recess  484  and end slot  488 . The firing pin recess and end slot  488  forming an L slot having an L shape defined by the L shaped planar tail surface  991 , along with the corresponding end ramp  486 . 
     In some embodiments, the present invention relates to a bolt action AR upper assembly as shown in the figures. The bolt action AR upper assembly can include a bolt action AR upper receiver as shown in one of the figures. The bolt action AR upper assembly can include a bolt of one of the figures in the AR upper receiver. 
     In some embodiments, the invention can include a bolt action AR upper receiver as shown in the figures. 
     In some embodiments, the invention can include a bolt for a bolt action AR upper receiver as shown in the figures. 
     In some embodiments, a bolt action AR upper assembly as shown in the figures is configured to be compatible with an AR DPMS LR-308 pattern or Armalite AR-10 pattern. 
     In some embodiments, a bolt action AR upper assembly is configured to be connectable with an AR lower assembly via two connection points. 
     In some embodiments, the bolt action AR upper assembly is configured to be connectable with an AR-10 lower assembly. 
     In some embodiments, the bolt action AR upper assembly is configured to be connectable with an AR-15 lower assembly. 
     In some embodiments, a bolt action AR upper assembly is configured to be connectable with an AR lower assembly through a pivot pin system and a takedown pin system. 
     In some embodiments, a bolt action AR upper assembly or upper receiver can have an upper pivot pin receiver hole that couples with a lower pivot pin receiver hole of an AR lower assembly or lower receiver via a pivot pin. 
     In some embodiments, a bolt action AR upper assembly or upper receiver can have an upper takedown pin receiver hole that couples with a lower take down pin receiver hole of an AR lower assembly or lower receiver via a takedown pin. 
     In some embodiments, a bolt action AR upper assembly or upper receiver can have: an upper pivot pin receiver hole that couples with a lower pivot pin receiver hole of an AR lower assembly or lower receiver via a pivot pin; and an upper pivot pin receiver hole that couples with a lower pivot pin receiver hole of an AR lower assembly or lower receiver via a pivot pin. 
     In some embodiments, a bolt for a bolt action AR upper receiver that couples with an AR lower receiver is provided. The bolt can include a unitary body having: a bolt head at one end that includes bolt head lugs separated by bolt head reliefs; an end opposite of the bolt head that includes an end slot that widens into a hammer slot, wherein an end ridge borders the end slot on one side so that an end ramp transitions from the end ridge to the hammer slot; a bolt neck separates the bolt head from a bolt body that extends to the opposite end; and the bolt body includes a bullet pushing ridge extending from the bolt neck toward the opposite end and traverses the bolt body until reaching a bullet pushing slope that slopes to a hammer ridge, wherein the hammer ridge extends to the end slot and hammer slot. In one aspect, the bolt can include a magazine recess laterally adjacent to the bullet ridge. In one aspect, the bolt can include a bolt handle hole for receiving a bolt handle. In one aspect, the bolt can include a bolt handle in the bolt handle hole. In one aspect, the bolt can include a firing pin within a firing pin recess in the bolt, wherein the firing pin recess opens into the end slot. 
     In some embodiments, a bolt action upper receiver can be configured to couple with an AR lower receiver. The bolt action upper receiver can include a unitary body having: a barrel end having a threaded receiver; a bolt receiving end opposite of the threaded receiver; an internal chamber extending from the bolt receiving end to the barrel end that is adapted to slidably receive a bolt therein so that the bolt can slide during actuation; a bolt handle slot extending from the bolt receiving end to a bolt rest recess, wherein the bolt handle slot opens from the internal chamber, the bolt rest recess being orthogonal with the bolt handle slot; an extractor ramp at an end of the bolt handle slot opposite of the bolt receiving end, the extractor ramp transitioning from a side of the bolt handle slot to the bolt rest recess; an ejector port opening from the internal chamber and being positioned between the bolt handle slot and barrel end; a magazine slot on the bottom of the unitary body that opens from the internal chamber, where the magazine slot narrows to a hammer slot toward the bolt receiving end; an upper pivot pin receiver hole at the barrel end; and an upper takedown receiver hole at the bolt receiving end. In one aspect, the bolt action upper receiver can include a picatinny rail opposite of the magazine slot. In one aspect, the picatinny rail has a 20 MOA slope. 
     In some embodiments, a bolt action upper assembly is provided that couples to an AR lower assembly. The bolt action upper assembly can include: the bolt action upper receiver of one of the embodiments; and the bolt of one of the embodiments within the receiver lumen of the bolt action upper receiver. 
     In some embodiments, a bolt action AR rifle can include: a standard AR lower assembly having a lower pivot pin receiver hole and a lower takedown pin receiver hole; and a bolt action upper assembly of one of the embodiments coupled to the standard AR lower assembly by having a pivot pin in the upper and lower pivot pin receiver holes and a takedown pin in the upper and lower takedown pin receiver holes. 
     In some embodiments, a method of converting an AR rifle to a bolt action AR rifle can include: removing a standard AR upper assembly from a standard AR lower assembly; and mounting the bolt action upper assembly of one of the embodiments to the standard AR lower assembly by placing a pivot pin in the upper and lower pivot pin receiver holes and a takedown pin in the upper and lower takedown pin receiver holes. 
     In some embodiments, a method of assembling a bolt action AR rifle can include: mounting the bolt action upper assembly of one of the claims to the standard AR lower assembly by placing a pivot pin in the upper and lower pivot pin receiver holes and a takedown pin in the upper and lower takedown pin receiver holes. 
     One skilled in the art will appreciate that, for this and other processes and methods disclosed herein, the functions performed in the processes and methods may be implemented in differing order. Furthermore, the outlined steps and operations are only provided as examples, and some of the steps and operations may be optional, combined into fewer steps and operations, or expanded into additional steps and operations without detracting from the essence of the disclosed embodiments. 
     The present disclosure is not to be limited in terms of the particular embodiments described in this application, which are intended as illustrations of various aspects. Many modifications and variations can be made without departing from its spirit and scope, as will be apparent to those skilled in the art. Functionally equivalent methods and apparatuses within the scope of the disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the foregoing descriptions. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting. 
     With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity. 
     It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to embodiments containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.” 
     In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group. 
     As will be understood by one skilled in the art, for any and all purposes, such as in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations of subranges thereof. Any listed range can be easily recognized as sufficiently describing and enabling the same range being broken down into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each range discussed herein can be readily broken down into a lower third, middle third and upper third, etc. As will also be understood by one skilled in the art all language such as “up to,” “at least,” and the like include the number recited and refer to ranges which can be subsequently broken down into subranges as discussed above. Finally, as will be understood by one skilled in the art, a range includes each individual member. Thus, for example, a group having 1-3 cells refers to groups having 1, 2, or 3 cells. Similarly, a group having 1-5 cells refers to groups having 1, 2, 3, 4, or 5 cells, and so forth. 
     From the foregoing, it will be appreciated that various embodiments of the present disclosure have been described herein for purposes of illustration, and that various modifications may be made without departing from the scope and spirit of the present disclosure. Accordingly, the various embodiments disclosed herein are not intended to be limiting, with the true scope and spirit being indicated by the following claims.