Abstract:
An improved bolt, bolt carrier and barrel assembly for rifles is described. This invention provides bolt mechanism that has heavier lugs on each side of the extractor to distribute the forces more equally and reliably and thereby reducing firearm failure rate. Moreover, this invention provides a bolt system that is easily adaptable to different ammunition feed devices as well as different ammunition cartridges. This invention further includes a barrel having a barrel extension designed to mate to the symmetrical bolt head lugs of this invention.

Description:
This application claims the benefit of provisional application No. 60/117,482, field Jan. 27, 1999 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to components for weapon system. More specifically, this invention relates to multi-lugged bolts, bolt carriers, and barrels for rifles. 
     2. Description of Related Art 
     A wide variety of bolt, bolt carriers and barrels are well known in the art. Typically such devices have lugs of the same size, regardless of the load bearing on the lugs, and which are evenly spaced around the face of the bolt, with the possible exception of the area required for the extractor. The following well known rifles have multi-lugged bolts and bolt carriers: the Johnson Model 1941 rifle and machine gun developed by Melvin Johnson; the M16/AR15 and Stoner 63 Weapons System developed by Eugene Stoner; the AR18 Rifle developed by Armalite; the Daewoo military and Sporting Rifles developed by the Korean company Daewoo; and the Steyer AUG rifle made in Austria. Other similar rifles are well known in the art. 
     SUMMARY OF THE INVENTION 
     It is desirable to provide a bolt and bolt carrier for rifles that permits ammunition to be fed from a variety of ammunition feeding devices, such as box magazines, clip magazines and ammunition belts while providing improved fatigue strength during the firing sequence. It is also desirable to provide a bolt and bolt carrier device that can be easily adapted in the field by the operator without the use of special tools to reconfigure the gun to fire a variety of cartridges, including but not limited to: 0.223 Rem (5.56×45 mm); 7.62×39 mm; and 5.45×39 mm. It is desirable to provide a bolt carrier that is designed to accept the bolt and to glide over a variety of magazines. In particular, it is desirable to provide a bolt with improved lug strength and failure resistance. 
     Therefore, it is the general object of this invention to provide an improved bolt and bolt carrier for automatic rifles that is compatible with receiving ammunition from a variety of feeding devices. 
     It is a further object of this invention to provide an improved bolt and bolt carrier for automatic rifles that can be easily adapted to fire a wide variety of well-known cartridges. 
     Another object of this invention to provide an improved bolt and bolt carrier for automatic rifles with improved lug strength and durability. 
     A still further object of this invention to provide an improved bolt and bolt carrier for automatic rifles that has an improved failure rate. 
     A further object of this invention to provide an improved bolt and bolt carrier for automatic rifles that has heavier lugs on each side of the extractor, that are adapted to receive without failure additional loading. 
     These and other objects of this invention are achieved by the invention as described herein. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front view of the preferred bolt carrier and bolt of this invention. 
     FIG. 2 is a left side view of the preferred bolt carrier and bolt of this invention. 
     FIG. 3 is a right side view of the preferred bolt carrier and bolt of this invention. 
     FIG. 4 is a disassembled view of the major components of and related to the preferred bolt carrier and bolt of this invention. 
     FIG. 5 is a detailed drawing of the preferred bolt of this invention showing the preferred component parts. 
     FIG. 6 is a detailed mechanical drawing showing the preferred lug placement and relative sizes of the lugs and gaps of the preferred bolt of this invention. 
     FIG. 7 is a perspective view of the lug mating between the preferred bolt and the barrel extension bolt head cavity of this invention. 
     FIG. 8 is a perspective view of the preferred barrel assembly of this invention. 
     FIG. 9 is a side section view of the bolt head cavity of the preferred barrel of this invention. 
     FIG. 10 is an end view of the preferred barrel bolt head—bolt interface of this invention. 
     FIG. 11 is an end view of the preferred barrel bolt head—bolt interface of this invention showing the bolt being rotated into engagement. 
     FIG. 12 is an end view of the preferred barrel bolt head—bolt interface showing the lug interaction between the bolt and the bolt head. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the figures and particularly to FIG. 1 showing the preferred bolt carrier  100  with the preferred bolt  101  inserted in the bolthole (not shown). The bolt carrier  100  has an operation rod hole  103  with an operation rod catch  102  for receiving and retaining the operation rod. The preferred bolt  101  is provided with six lugs  601 ,  603 ,  605 ,  607 ,  609 ,  611  on the bolt head  201 . An extractor  104  as well as an ejector slot  106  are provided generally opposite each other on the bolt head  201 . Indentations  105   a ,b are provided to permit the bolt carrier  100  to fit to a wide variety of ammunition magazines. 
     FIG. 2 shows the left side view of the preferred bolt carrier  100  and bolt  101  of this invention. The bolt head  201  is shown fixed to the end of the bolt shaft  204 . A cam slot  202  is provided on the left side of the bolt carrier  100 , through which a cam pin  203  can be seen. The operation rod hole  103  is also shown in perspective view. 
     FIG. 3 shows the right side view of the preferred bolt carrier  100  of this invention. This view provides additional detail as to the bolt lug head  201  of this invention. 
     FIG. 4 shows the major components and related components of the preferred bolt carrier  100  and bolt  101  of this invention in disassembled but close proximity to each other. The bolt  101  is shown with the bolt head  201  extended away from the bolthole  307  in the bolt carrier  100 . A cam  301  is shown adapted to mechanically interact with the bolt  101  through the cam slot  202 . An operation rod catch  302  is provided, which is insertable into the catch opening  308  in the bolt carrier  100 . A bolt catch retension pin  303  is provided to hold the operation rod catch  302  in place by insertion into the pin hole  309  after inserting the operation rod catch  302  in the bolt carrier  100 . A firing pin  305  is provided with a carrier end  306 , both of which are adapted to be held in place within the bolt carrier  100  by a carrier end pin  304  which is inserted into an carrier pin hole  310 , after insertion of the firing pin  305  and carrier end  306 , thereby holding each in place. 
     FIG. 5 shows a detailed perspective view of the preferred bolt  101  of this invention. An extractor  505  is fixed to the bolt  101  by an extractor pin  501 , which is adapted to be positioned inside  506  the bolt  101  with each end  507  and  508  pressed through pin holes  503  and  502  respectively. A spring  504  is provided to give tension to the extractor  505 , while simultaneously holding the extractor pin  501  in place. The extractor pin  501  is stepped  509  and  510  to keep the extractor pin  501  in place. 
     FIG. 6 shows the detailed mechanical drawing of the bolt head  201  face of the preferred bolt  101  with each lug  601 ,  603 ,  605 ,  607   609  and  61  land lug space  602 ,  604 ,  606 ,  608 ,  610  and  612  shown. The extractor slot  104  is shown at the top of the bolt head  201  with the ejector slot  106  shown generally at the bottom of the bolt head  201 . The relative sizes and positions of the six lugs  601 ,  603 ,  605 ,  607 ,  609 ,  611  are important to this invention. For example, the top two lugs  601  and  611  on either side of the extractor slot  104  are generally the same size  622  and  623  and are generally wider than the other lugs  603 ,  605 ,  607 ,  609 , each of which is generally the same size  624 ,  625 ,  626 ,  627 . In the preferred embodiment of this invention, the bolt head  201  lugs  601 ,  603 ,  605 ,  607 ,  609 ,  611  are symmetrically positioned about the axis  613 , with the gaps between the respective lugs matched. For example, the preferred gap  602  between the lugs  601  and  603  is generally the same width as the gap  610  between the lugs  609  and  611 . The preferred gap  604  between lugs  603  and  605  is generally the same width as the gap  608  between the lugs  607  and  609 . The largest gap  612  is between the extractor slot  104  and the second largest gap  606  is over the ejector slot  106 . Also, in the preferred embodiment of the bolt head  201  of this invention the distance from axis  613  to point  616  is generally the same as the distance from axis  613  to point  614 , and the distance from axis  613  to point  617  is generally the same as the distance from axis  613  to point  615 . In this way the design of the preferred bolt head is generally symmetrically. The reader should note that while the ejector slot  106  is shown somewhat closer to lug  605  than lug  607 , alternatively, the ejector  106  can be orientated closer to lug  607  or can be positioned at an equal distance from lug  605  and  607 . 
     This bolt head  201  is designed to fit to the barrel extension  701 , which has a bolt head cavity  703  having protrusions where the bolt head  201  has lugs and lugs where the bolt head  201  has spaces. 
     FIG. 7 shows a perspective view of the preferred mating between the bolt head  201  and the bolt head cavity  703  of the barrel extension  701 , showing how the bolt head  201  lugs  601 ,  603 ,  605 ,  607 ,  609 ,  611  mate with bolt head cavity  703  gaps  704 ,  705 ,  706 ,  707 , 708 , 709 . 
     FIG. 8 shows a perspective view of the preferred barrel  800  having a sight  801  attached. Detail of the bolt head cavity  703  with the gaps  704 ,  705 ,  706 ,  707 ,  708 ,  709  are shown. 
     FIG. 9 shows a cut-away view of the barrel  800  bolt head cavity  703  showing the chamber  901 . 
     FIG. 10 shows an interior cut-away view of the bolt head cavity  703  with the bolt head  201 , with the bolt head  201  lugs  601 ,  603 ,  605 ,  607 ,  609 ,  611  inserted in the gaps  704 ,  705 ,  706 ,  707 ,  708 ,  709  of the bolt head cavity  703 . 
     FIG. 11 shows the interior cut-away view of the bolt head cavity  703  with the bolt head  201  inserted and rotated. 
     FIG. 12 shows the interior cut-away view of the bolt head cavity  703  with the bolt head  201  inserted and rotated as well as showing the relative positions of the extractor  104  and the ejector  106 . 
     The foregoing description is of a preferred embodiment of the invention and has been presented for the purposes of illustration and as a description of the best mode of the invention currently known to the inventors. It is not intended to be exhaustive or to limit the invention to the precise form, connections, or choice of components disclosed. Obvious modifications or variations are possible and foreseeable in light of the above teachings. This embodiment of the invention was chosen and described to provide the best illustration of the principles of the invention and its practical application to thereby enable on of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. All such modifications and variations are within the scope of the invention as determined by the appended claims when they are interpreted in accordance with the breadth to which they are fairly, legally and equitably entitled.