Patent Publication Number: US-10317172-B1

Title: In-chamber laser boresight device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Application Ser. No. 62/385,317, filed Sep. 9, 2016, entitled UNIQUE AND NOVEL LASER BORESIGHT DEVICE AND METHOD FOR USING DESCRIBED LASER BORESIGHT DEVICE FOR THE SIGHTING-IN AND ZEROING OF RIFLES OF THE M-16, AR-15 AND SIMILAR DESIGN AND IN ANY CALIBER, naming Wayne B. Morgan, Richard D. Lindlau, and Daniel R. A. Harder as inventors, which is incorporated herein by reference in the entirety. 
    
    
     TECHNICAL FIELD 
     The present disclosure is related generally to the field of firearm sighting and, more particularly, to laser boresight devices. 
     BACKGROUND 
     Boresight devices facilitate the alignment of a barrel of a firearm to a sighting device, or “boresighting” the firearm. Boresighting is typically used to provide efficient zeroing (or sighting in) of a firearm, which consists of aligning the point of impact of a bullet with a point of aim of a sighting device. 
     The trajectory of a bullet from a firearm may generally depend on a variety of factors such as, but not limited to, firearm type, bullet caliber, bullet speed, target distance, wind direction, and wind speed. Zeroing may typically include firing one or more rounds of ammunition at a target and aligning the sighting device to the point of impact. If the sighting device is far from alignment, multiple zeroing iterations may be required. However, this process may be time-consuming and waste costly ammunition. 
     Boresight devices may provide efficient zeroing by providing an initial alignment of the sighting device to the barrel. For example, a boresight device may typically be used to align the barrel to a sighting device for a target at a selected distance (e.g., 25 meters) at which a bullet trajectory may approximate a straight line from the barrel to the target. A user may then further refine the sighting alignment to zero the firearm at any distance to account for deviations of the bullet trajectory. 
     However, typical boresight devices may be cumbersome, inaccurate, difficult to align, and/or may suffer from limited battery life. It is therefore desirable to provide systems and methods for improved boresighting. 
     SUMMARY 
     A boresight device is disclosed, in accordance with one or more illustrative embodiments of the present disclosure. In one illustrative embodiment, the boresight device includes a casing designed to be loaded into a chamber of a firearm in the place of a bolt carrier group. The casing may include one or more keyed features to engage with corresponding components of the firearm such that the one or more keyed features align an exit port in the casing to a barrel of the firearm upon loading of the casing into the chamber. In another illustrative embodiment, the boresight device includes a laser device configured to generate a laser beam. The laser device may be positioned within the casing to direct the laser beam through the exit port of the casing and along an axis of the barrel when the casing is loaded into the chamber. 
     A boresight device is disclosed, in accordance with one or more illustrative embodiments of the present disclosure. In one illustrative embodiment, the boresight device includes a casing designed to be loaded into a chamber of a firearm in the place of a bolt carrier group. The casing may be designed to accept a laser device for generating a laser beam. The casing may include one or more keyed features to engage with corresponding components of the firearm to align an exit port in the casing to a barrel of the firearm upon loading of the casing into the chamber such that the laser beam propagates through the exit port along an axis of the barrel. 
     A boresight device comprising is disclosed, in accordance with one or more illustrative embodiments of the present disclosure. In one illustrative embodiment, the boresight device includes a casing designed to be loaded into a chamber of a firearm in the place of a bolt carrier group. The casing may include one or more keyed features to engage with corresponding components of the firearm such that the one or more keyed features align an exit port in the casing to a barrel of the firearm upon loading of the casing into the chamber. In another illustrative embodiment, the boresight device includes a user-swappable laser device configured to generate a laser beam. The user-swappable laser device may further be positioned within the casing to direct the laser beam through the exit port and along an axis of the barrel when the casing is loaded into the chamber. In another illustrative embodiment, the boresight device includes a laser power actuator providing a user-accessible interface for actuating the user-swappable laser device when the casing is loaded into the chamber. In another illustrative embodiment, the boresight device includes a removable cap providing access for removal and insertion of the user-swappable laser device. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not necessarily restrictive of the invention as claimed. The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention and, together with the general description, serve to explain the principles of the invention. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       The numerous advantages of the disclosure may be better understood by those skilled in the art by reference to the accompanying figures in which: 
         FIG. 1  is an exploded perspective view of a boresight device, in accordance with one or more embodiments of the present disclosure. 
         FIG. 2  is an exploded orthogonal view of a boresight device, in accordance with one or more embodiments of the present disclosure. 
         FIG. 3  is an orthogonal assembled view of a boresight device, in accordance with one or more embodiments of the present disclosure. 
         FIG. 4  is an exploded side view of an M-16 firearm in an opened position illustrating a bolt carrier group and a charging handle removed to provide access to a chamber of the firearm, in accordance with one or more embodiments of the present disclosure. 
         FIG. 5  is a perspective cut-out view of an empty chamber of a firearm, in accordance with one or more embodiments of the present disclosure. 
         FIG. 6  is a cut-out view of a chamber illustrating a loaded boresight device, in accordance with one or more embodiments of the present disclosure. 
         FIG. 7  is a side view of a firearm with a loaded boresight device, in accordance with one or more embodiments of the present disclosure. 
         FIG. 8  is a flow diagram illustrating a method for boresighting a firearm using a boresight device, in accordance with one or more embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to the subject matter disclosed, which is illustrated in the accompanying drawings. The present disclosure has been particularly shown and described with respect to certain embodiments and specific features thereof. The embodiments set forth herein are taken to be illustrative rather than limiting. It should be readily apparent to those of ordinary skill in the art that various changes and modifications in form and detail may be made without departing from the spirit and scope of the disclosure. 
     Embodiments of the present disclosure are directed to systems and methods for boresighting a firearm by loading a boresight device into the chamber of a firearm in the place of a bolt carrier group, whereupon the boresight device may propagate a laser beam through the barrel of the firearm for alignment with a sighting device. 
     Boresighting typically requires two stages of alignment to properly align a sighting device to the barrel of a firearm. First, a boresight device must be aligned to the barrel. For example, a laser boresight device must be aligned such that a laser beam may propagate along an axis of the barrel (e.g., a center axis of the barrel, an axis parallel to the center axis, or the like). Second, the sighting device must be aligned to the point of impact of the laser beam on a target at a selected distance. 
     Embodiments of the present disclosure are directed to a laser boresight device designed to be loaded into the chamber of a firearm. In this regard, the laser boresight device may direct a laser beam through the length of the barrel towards a target. Additional embodiments of the present disclosure are directed to a boresight device with one or more keyed features that engage with corresponding features of the firearm to provide self-alignment of the laser beam with an axis of the barrel when loaded into the firearm. 
     Additional embodiments of the present disclosure are directed to a boresight device designed to be loaded into the chamber of a firearm in the place of a bolt carrier group. Many firearms, such as, but not limited to, M-16 rifles, AR-15 rifles, or the like include a bolt carrier group that may be easily and quickly removed to provide access to the chamber. Further, the dimensions and features of the bolt carrier group are keyed to provide self-alignment within the chamber for reliable operation. For example, the bolt carrier group may be generally cylindrically shaped with an outer diameter closely matched to the inner diameter of the chamber such that the bolt carrier group may controllably slide back and forth within the chamber during firing with minimal wobble. Further, the bolt carrier group may include one or more rails, grooves, protrusions, cut-outs, or the like to engage with components such as, but not limited to, the charging handle, the end face of the barrel, or a gas return line. 
     Embodiments of the present disclosure are directed to a boresight device having dimensions and/or keyed features to engage with the firearm in a similar manner as a bolt carrier group. In this regard, the boresight device may self-align the path of a laser beam to the axis of the barrel when loaded into the chamber without additional alignment by the user. 
     It is recognized herein that a boresight device providing self-alignment with the barrel of a firearm (e.g., the first alignment step of boresighting) may facilitate efficient operation of the boresight device itself without the need for user training on the operation of the device. For example, a user may simply remove the bolt carrier group, insert the boresight device, power on the laser beam, aim the laser beam at the target, and align the sighting device to the target (e.g., the second alignment step of boresighting). Further, a boresight device providing self-alignment with the barrel of the firearm may be rapidly switched between multiple firearms. Accordingly, the boresight device may be used to boresight many (e.g., greater than 100) firearms in a day and may thus be suitable for reliable and fast in-field military operations. 
     It is further recognized herein that a laser boresight device inserted into the chamber in the place of a bolt carrier group may provide highly accurate self-alignment of the laser beam with the axis of the barrel with without the time, effort, or uncertainty associated with manually aligning the boresight device to the barrel during the first alignment step. Accordingly, a boresight device inserted into the chamber in the place of a bolt carrier group may provide a higher accuracy than typical laser boresight devices such as, but not limited to, those placed within the firing end of a barrel or those shaped as bullets and loaded into the firearm. For example, boresight devices inserted into the firing end of the rifle may sag due to weight protruding from the end of the barrel, loose fit within the barrel, or the like. Further, boresight devices inserted into the barrel pose a risk of physically damaging the barrel (e.g., via abrasions, chips, or the like), particularly through repeated use, that may ultimately reduce the firing accuracy of the firearm. By way of another example, boresight devices shaped as ammunition loaded into the firearm may have dimensions that do not precisely match the inner diameter of the barrel and/or do not precisely match the type of ammunition to be used, which may lead to inaccurate alignment and unreliable operation. In contrast, a boresight device inserted into the chamber in the place of a bolt carrier group may be rigidly fixed within the chamber (e.g., by pressure from the recoil spring, snug fit within the chamber, keyed features, or the like) and may thus not exhibit sag and/or wobble that may lead to alignment errors. Further, the length of a boresight device designed to replace a bolt carrier group may be, but is not required to be, 30-50 millimeters, which may provide substantial interaction length with the chamber for accurate self-alignment with the firearm. 
     Additional embodiments of the present disclosure are directed to a boresight device with laser power switch accessible when loaded into the chamber of a firearm. For example, the boresight device may have a laser power switch accessible through a chamber door. By way of another example, the boresight device may have a laser power switch that may be actuated by a component of the firearm such as, but not limited to, the safety switch or the trigger/hammer. In this regard, a user may selectively actuate the power of the laser with the device inserted into the firearm, which may facilitate safe operation and minimize stray reflections of the laser beam into the eyes of the user and/or any bystanders. 
     The boresight device may be powered by any power source known in the art such as, but not limited to, batteries (e.g., single-use or rechargeable) or an external power supply. It is recognized herein that a boresight device designed to be loaded into the chamber in the place of a bolt carrier group may be powered by long-lasting and/or rechargeable batteries suitable for extended use, which may facilitate prolonged field use of the boresight device. In particular, boresight device the size of a bolt carrier group may be, but is not required to be, sufficient to provide for a wide variety of battery form factors such as, but not limited to, C, AA, AAA, AAAA, or button. 
     It is further recognized herein that a boresight device may be used for a variety of purposes beyond zeroing a firearm. For example, a boresight device in which a laser beam may be selectively actuated by the user (e.g., via the trigger) may provide ammunition-less training in which a point of impact of the laser beam is gauged as a fire rather than the point of impact of a round of fired ammunition. 
     Referring now to  FIGS. 1 through 3 , a boresight device designed to be loaded into a chamber of a firearm is generally shown.  FIG. 1  is an exploded perspective view of a boresight device  100 , in accordance with one or more embodiments of the present disclosure.  FIG. 2  is an exploded orthogonal view of the boresight device  100 , in accordance with one or more embodiments of the present disclosure.  FIG. 3  is an orthogonal assembled view of the boresight device  100 , in accordance with one or more embodiments of the present disclosure. 
     In one embodiment, the boresight device  100  includes a laser device  102  suitable for generating a laser beam  104 . Further, the laser beam  104  may include any wavelength or combination of wavelengths. For example, the laser device  102  may generate a laser beam  104  including one or more visible wavelengths such as, but not limited to, red, yellow, green, or blue wavelengths. Such wavelengths are typically visible to the human eye and may be readily seen on an alignment target. By way of another example, the laser device  102  may generate a laser beam  104  including one or more wavelengths typically not detectable with the human eye such as, but not limited to, infrared (IR) wavelengths. In one instance, the laser beam  104  may include infrared wavelengths that may be classified as “eye-safe” at certain power levels (e.g., due to an inability of the human eye to focus a beam of such light onto the retina). In this case, the laser beam  104  may generate visible light when incident on a target through fluorescence or a similar process. Alternatively, the laser beam  104  may be viewed using additional viewing equipment such as, but not limited to, an IR camera, or an IR viewer (e.g., a “night-vision” viewer). 
     The laser device  102  may be any type of laser suitable for generating the laser beam  104 . In one embodiment, the laser device  102  includes a laser diode suitable for directly generating laser light at a desired wavelength. For example, the laser device  102  may include an aluminum-gallium-indium-phosphide (AlGaInP) laser diode for generating a laser beam at wavelengths in the range of 630-650 nm, or red wavelengths. In another embodiment, the laser device  102  includes a diode-pumped solid-state (DPSS) laser in which a laser diode generates light that pumps a solid-state material (e.g., a crystal) that in turn generates wavelengths of interest (e.g., 671 nm). In another embodiment, the laser device  102  may include a gas laser such as, but not limited to, a helium-neon laser. In another embodiment, the laser device  102  includes a frequency-conversion component to generate one or more desired wavelengths through nonlinear optical interactions such as, but not limited to, frequency doubling or four-wave mixing. For example, green laser light at a wavelength of 532 nm may be, but is not required to be, generated by a three-step DPSS process in which a laser diode emits 808 nm light, which pumps a nonlinear crystal (e.g., neodymium-doped yttrium aluminum garnet (Nd:YAG), neodymium-doped yttrium orthovanadate (Nd:YvO 4 ), or the like) to generate 1064 nm laser light, which is then frequency-doubled in a nonlinear crystal (e.g., lithium triborate (LBO), potassium titanyl phosphate (KTP), or the like) to generate the 532 nm laser light. Similar processes may be utilized to generate any desired wavelength or range of wavelengths by the laser device  102 . In a general sense, the laser device  102  may utilize any mechanism to generate a laser beam  104  suitable for boresighting. 
     The laser device  102  may be powered by any power source known in the art such as, but not limited to, batteries (e.g., single-use or rechargeable) or an external power supply. For example, batteries suitable for powering the boresight device may include, but are not limited to, alkaline, silver cell, nickel-cadmium, lithium-ion, or zinc-carbon. Further, batteries suitable for powering the boresight device may have any shape or form-factor known in the art, such as, but not limited to, C, AA, AAA, AAAA, or button. 
     In another embodiment, the laser device  102  includes a laser power actuator  106 . The laser power actuator  106  may include any component known in the art suitable for providing a user interface for the adjustment of the power of the laser beam  104  such as, but not limited to, a button, a switch, or a dial. For example, the laser power actuator  106  may toggle the laser beam  104  on and off. By way of another example, the laser power actuator  106  may provide intensity control of the laser beam  104 . Further, the laser power actuator  106  may be accessible on the exterior of the casing  108  such that a user may interface with the laser power actuator  106  while the boresight device  100  is fully assembled. In another embodiment, the laser power actuator  106  includes a wireless transmitter/receiver suitable for providing wireless control of the laser beam  104 . For example, the laser power actuator  106  may operate wirelessly using any frequency and/or protocol known in the art such as. For example, the laser power actuator  106  may include a radio frequency (RF) transmitter/receiver operating on any frequency such as, but not limited to 315 MHz. By way of another example, the laser power actuator  106  may include a Bluetooth transmitter/receiver. 
     In another embodiment, the boresight device  100  includes a casing  108  to house the laser device  102 . For example, the casing  108  casing may include an enclosure with a cavity  110  suitable for containing the laser device  102 . The casing  108  may be fabricated from any material suitable for insertion into the chamber of a firearm. For example, the casing  108  may be fabricated at least in part out of a metal such as, but not limited to, aluminum or stainless steel. Further, the casing  108  may be treated with a coating and/or a hardening process (e.g., peening, or the like), which may provide increased durability and/or reliable operation for many uses. By way of another example, the casing  108  may be fabricated at least in part out of glass-filled nylon. 
     In another embodiment, the casing  108  includes an exit port  112  to allow the laser beam  104  generated by the laser device  102  to propagate out of the casing  108 . For example, the exit port  112  may include an open hole through which the laser beam  104  may propagate. By way of another example, the exit port  112  may include a window formed from a material at least partially transparent to the wavelength of the laser beam  104 . The window may be formed from any material known in the art suitable for transmitting a laser beam  104  such as, but not limited to, a glass (e.g., fused silica, borosilicate glass, or the like), a crystal (e.g., quartz, sapphire, or the like), or a plastic material. 
     In another embodiment, the boresight device  100  includes one or more laser positioning devices  114 . For example, as illustrated in  FIGS. 1-3 , the one or more laser positioning devices  114  may include a guide lug  116  to mechanically couple the laser device  102  to the casing  108 . In this regard, the interior portion  118  of the guide lug  116  may accept at least a portion of the laser device  102  and an exterior portion  120  of the guide lug  116  may couple with an interior wall of the casing  108 . Accordingly, the guide lug  116  may secure may secure the laser device  102  within the casing  108 . By way of another example, though not shown, the one or more laser positioning devices  114  may include one or more adjustable components (e.g., alignment screws, or the like) to adjust the path of the laser beam  104 . In this regard, a user may adjust the direction that the laser beam  104  exits the exit port  112 . 
     In another embodiment, as illustrated in  FIGS. 1-3 , the casing  108  includes a removable end cap  122  to provide access to the cavity  110  of the boresight device  100 . For example, the end cap  122  may provide a user with access to insert, remove, and/or adjust the laser device  102 . A user may thus selectively replace the laser device  102  to provide a laser beam  104  with a selected output wavelength, a selected laser intensity, or the like. In one instance, an adjustable guide lug  116  may accommodate multiple laser devices  102  with different form factors. In another instance, a dedicated guide lug  116  may be used for each form factor. Further, the end cap  122  may provide a user with access to insert, remove, and/or replace a battery to power the laser device  102 . In another embodiment, though not shown, the boresight device  100  includes an integrated laser device  102 . For example, the laser device  102  may not be removable. Further, the casing  108  may be configured without a removable guide lug  116  and may directly couple to the integrated laser device  102 . 
     In another embodiment, the boresight device  100  includes one or more optical elements to control and/or modify the laser beam  104  from the laser device  102  such as, but not limited to one or more lenses, filters, or polarizers. The one or more optical elements may be integrated within any component the boresight device  100  such as, but not limited to, the laser device  102  itself, the cavity  110 , the guide lug  116 , or the exit port  112 . For example, the boresight device  100  may include one or more filters to modify the spectral or spatial characteristics of the laser beam  104 . In one instance, the boresight device  100  may include a spectral filter to at least partially reduce the intensity of one or more wavelengths of light generated by the laser device  102 . For example, a laser device  102  including a nonlinear crystal may output a desired wavelength (e.g., visible green or blue wavelengths) as well as unconverted wavelengths (e.g., IR wavelengths). Accordingly, a spectral filter may selectively transmit the desired wavelengths and reflect and/or absorb undesired wavelengths. In another instance, the boresight device  100  may include a spatial filter and/or one or more optical elements to shape the beam profile of the laser beam  104 . 
     Referring now generally to  FIGS. 4 through 7 , the coupling of a boresight device  100  with a chamber of an M-16-style firearm is shown.  FIGS. 4 and 5  illustrate an M-16-style firearm suitable for receiving a boresight device  100 .  FIGS. 6 and 7  illustrate a boresight device  100  loaded within the firearm. It is to be understood, however, that  FIGS. 4 through 7  and the accompanying descriptions are provided solely for illustrative purposes and should not be interpreted as limiting the present disclosure. The boresight device  100  may be designed to be loaded into the chamber of a firearm of any style and of any caliber. For example, the boresight device  100  may be designed to be loaded into any M-16 or AR-15 style firearm or derivatives thereof. By way of another example, the boresight device  100  may be designed to be loaded into additional styles of firearms without departing from the spirit and scope of the present disclosure. 
       FIG. 4  is an exploded side view of an M-16 firearm  402  in an opened position illustrating a bolt carrier group  404  and a charging handle  406  removed to provide access to a chamber  408  of the firearm, in accordance with one or more embodiments of the present disclosure. For example, the chamber  408  may be accessed by removing a locking pin  410 , pivoting open the firearm  402 , and removing the bolt carrier group  404  with the charging handle  406 . In  FIG. 4 , a chamber door  412  is opened to view the interior of the chamber  408 .  FIG. 5  is a perspective cut-out view of an empty chamber  408  of a firearm  402 , in accordance with one or more embodiments of the present disclosure. 
     In one embodiment, the boresight device  100  is designed to be loaded into the chamber  408  in the place of the bolt carrier group  404 . For example, a user may use the charging handle  406  to insert and/or remove the boresight device  100  from the chamber  408  in the same manner as the bolt carrier group  404 . 
       FIGS. 6 and 7  illustrate multiple views of the boresight device  100  loaded in the chamber  408  of the firearm  402  and the path of the laser beam  104  during operation.  FIG. 6  is a cut-out view of the chamber  408  illustrating a loaded boresight device  100 , in accordance with one or more embodiments of the present disclosure.  FIG. 7  is a side view of the firearm  402  with a loaded boresight device  100 , in accordance with one or more embodiments of the present disclosure. 
     In one embodiment, the chamber  408  may be bounded by the barrel  414  towards the firing end of the firearm  402 , a recoil buffer  416  towards the butt of the firearm  402 , and a chamber wall  418  on the sides. 
     In another embodiment, the boresight device  100  is designed to be loaded into the chamber of a firearm (e.g., firearm  402 , or the like) such that the exit port  112  self-aligns with the axis of the barrel of the firearm upon loading. In this regard, the laser beam  104  generated by the laser device  102  may propagate along the axis of the barrel  414  and out the firing end of the barrel  414 . A user may thus immediately align the laser beam  104  on a target at a selected distance and align a sighting device to the laser beam  104  to boresight the firearm without alignment of the laser device  102  to the barrel  414 . 
     The boresight device  100  may include one or more keyed features to facilitate the alignment of the exit port  112  with the axis of the barrel of the firearm when loaded into the chamber  408 . 
     In one embodiment, the one or more keyed features include the outer dimensions of the boresight device  100  (e.g., the outer dimensions of the casing  108 . For example, the outer dimensions of the boresight device  100  (e.g., the casing  108 ) may correspond to those of the bolt carrier group  404  such that the boresight device  100  may be firmly secured into the chamber  408  in a fixed position. In this regard, the laser device  102  may be roughly the shape of a cylinder with a diameter approximating that of the bolt carrier group  404 . Further, the length of the bolt carrier group  404  may correspond to the length of the chamber  408 . In this regard, a front face  124  of the boresight device  100  including the exit port  112  may be proximate to or be in contact with the barrel  414 , and a rear face  126  may be in contact with the recoil buffer  416 . 
     In another embodiment, a portion of the boresight device  100  is designed to extend into the barrel  414  to facilitate self-alignment of the exit port  112  to the axis of the barrel  414  when loaded into the chamber  408 . For example, the casing  108  may include (e.g., as one or more chamfered edges  128  designed to contact one or more interior portions of the barrel such as, but not limited to, an end face  420 , one or more bolt grooves  422  (e.g., grooves designed to engage with a bolt during firing of the firearm  402 ), a bolt-receiving chamber  424 , a bullet-receiving chamber  426 , or the like. For example, a portion of the casing  108  may be formed in the shape of a bullet and may be configured to extend into the bullet-receiving chamber  426  of the barrel  414  to facilitate alignment of the boresight device  100  with the axis of the barrel  414 . Further, a portion of the casing  108  designed in the shape of a bullet may be removable. In this regard, a user may customize the portion of the casing  108  designed in the shape of a bullet to accommodate firearms suitable for firing any caliber of bullet. In another embodiment, though not shown, the boresight device  100  is designed to be loaded into the chamber  408 , but not protrude into the barrel  414 . 
     In another embodiment, the rear face  126  of the boresight device  100  is designed to engage with the recoil buffer  416  such that a recoil spring  428  firmly secures the boresight device  100  in the chamber  408 . Further, the boresight device  100  may contact portions of the chamber wall  418 , the barrel  414 , or the like to provide a secure fit and robust alignment. 
     In another embodiment, the boresight device  100  includes one or more keyed features (e.g., rails, grooves, protrusions, cut-outs, or the like) to engage with corresponding components of the firearm  402  to secure and/or align the boresight device  100  within the chamber  408 . For instance, keyed features of the boresight device  100  may include a rail assembly  130  and/or a notch  132  to engage with the charging handle  406 . In another instance, keyed features of the boresight device  100  may include a protrusion to engage with the gas return supply  430 . In another instance, keyed features of the boresight device  100  may include one or more grooves to engage with bolt grooves  422 . In another instance, keyed features of the boresight device  100  may include chamfered portions of the casing designed to extend into the barrel  414  to contact one or more portions of the interior of the barrel  414 . 
     In another embodiment, the laser power actuator  106  is accessible to a user when the boresight device  100  is loaded within the chamber  408  of the firearm  402 . For example, as illustrated in  FIG. 6 , the laser power actuator  106  may be accessible through the chamber door  412  when opened. By way of another example, the laser power actuator  106  may engage with the safety switch of the firearm  402 . In this regard, a user may utilize the safety switch to toggle the laser beam  104  and/or adjust the beam intensity. By way of a further example, the laser power actuator  106  may engage with the hammer  432  of the firearm  402 . In this regard, a user may toggle the laser beam  104  on and off by pulling the trigger  434 . 
     In another embodiment, the boresight device  100  includes a pressure-sensitive switch located on the rear face  126  of the boresight device  100 . Accordingly, pressure from the recoil buffer  416  provided by the recoil spring  428  when the boresight device  100  is loaded into the chamber  408  engage the pressure-sensitive switch. For example, the pressure-sensitive switch may toggle the laser beam  104  on only when the boresight device  100  is loaded and may toggle the laser beam  104  off otherwise. By way of another example, the pressure-sensitive switch may serve as a safety such that a user may only engage the laser power actuator  106  to toggle or adjust the intensity of the laser beam  104  only when the pressure-sensitive switch is engaged (e.g., when the boresight device  100  is loaded into the firearm  402 ). 
     In another embodiment, at least one laser positioning device  114  is accessible to a user when the boresight device  100  is loaded within the chamber  408  of the firearm  402 . For example, the at least one laser positioning device  114  may be accessible through the chamber door  412  when opened. In this regard, a user may make adjustments of the alignment of the laser beam  104  to the barrel  414  if required. For example, it may be the case that the boresight device  100  may not properly self-align during loading such that the laser beam  104  does not propagate along the axis of the barrel  414 . By way of another example, it may be the case that adjustments may be necessary based on the exact specifications of a particular firearm. Accordingly, a user may adjust the alignment as necessary. 
       FIG. 8  is a flow diagram illustrating a method  800  for boresighting a firearm using a boresight device, in accordance with one or more embodiments of the present disclosure. Applicant notes that the embodiments and enabling technologies described previously herein in the context of boresight device  100  should be interpreted to extend to method  800 . It is further noted, however, that the method  800  is not limited to the architecture of boresight device  100 . 
     In one embodiment, the method  800  includes a step  802  of replacing a bolt carrier group of a firearm with a boresight device (e.g., boresight device  100 ). For example, the boresight device may be loaded into the chamber in the place of a bolt carrier group. Accordingly, a user may first unload the bolt carrier group (e.g., with the charger handle), and replace the bolt carrier group with the boresight device. 
     In another embodiment, the boresight device includes a laser device for generating a laser beam and an exit port from which the laser beam may exit the boresight device. Further, the boresight device may self-align the exit port of the boresight device to the axis of the barrel when loaded into the chamber without requiring adjustment from the user. In this regard, the laser beam may propagate along the axis of the barrel and out the firing end of the barrel to indicate a direction at which the barrel is pointed. For example, the boresight device may have dimensions and/or keyed features designed to engage with components of the firearm during loading to align the exit port to the axis of the barrel. 
     In another embodiment, the method  800  includes a step  804  of directing a laser beam generated by a laser through the barrel of the firearm to a target at a selected distance from the firearm. In this regard, the user may establish the direction at which the barrel is pointed. 
     In another embodiment, the method  800  includes a step  806  of aligning a sighting device to a point of impact of the laser beam on the target. The user may thus align the sighting device to the barrel of the target. 
     In another embodiment, the method  800  includes a step  808  of replacing the boresight device with the bolt carrier group. After boresighting the firearm, the user may return the firearm to operational status such that the firearm is ready to fire ammunition. For example, the user may replace the boresight device with the bolt carrier group removed in step  802 . 
     As necessary, the user may further zero the firearm at any distance using any method known in the art. For example, the user may fire one or more rounds of ammunition and adjust the sight to the point of impact. It is recognized herein that boresighting the firearm using method  800  prior to firing ammunition may improve the speed at which firearms may be zeroed and reduce the amount of ammunition wasted during the zeroing process. 
     The herein described subject matter sometimes illustrates different components contained within, or connected with, other components. It is to be understood that such depicted architectures are merely exemplary, and that in fact many other architectures can be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively “associated” such that the desired functionality is achieved. Hence, any two components herein combined to achieve a particular functionality can be seen as “associated with” each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated can also be viewed as being “connected” or “coupled” to each other to achieve the desired functionality, and any two components capable of being so associated can also be viewed as being “couplable” to each other to achieve the desired functionality. Specific examples of couplable include but are not limited to physically interactable and/or physically interacting components and/or wirelessly interactable and/or wirelessly interacting components and/or logically interactable and/or logically interacting components. 
     It is believed that the present disclosure and many of its attendant advantages will be understood by the foregoing description, and it will be apparent that various changes may be made in the form, construction and arrangement of the components without departing from the disclosed subject matter or without sacrificing all of its material advantages. The form described is merely explanatory, and it is the intention of the following claims to encompass and include such changes. Furthermore, it is to be understood that the invention is defined by the appended claims.