US3257108A

US3257108A - Mounting of gun muzzle devices

Info

Publication number: US3257108A
Application number: US208732A
Authority: US
Inventors: Frank A Pachmayr; Walter R Nass
Original assignee: FIREARM ACCESSORIES Inc
Current assignee: PACHMAYR FRANK A; PACHMAYR NANITTA G; Pachmayr Gun Works Inc
Priority date: 1962-07-10
Filing date: 1962-07-10
Publication date: 1966-06-21
Anticipated expiration: 1983-06-21

Description

2 Sheets-Sheet 1 F. A. PACHMAYR ETAL MOUNTING OF GUN MUZZLE DEVICES INVENTORS FRANK A. PACA/MA v2 WALTEQ R NASS June 21, 1966 Filed July 10 1962 UbQ hw A TTO RNEY June 21, 1966 F. A. PACHMAYR ETAL 3,257,108

MOUNTING 0F GUN MUZZLE DEVICES Filed July 10, 1962 2 Sheets-Sheet 2 IN VEN TORS FRANK A. PACHMAVE IgALTEQ R- MASS ATTORNEV 3,257,108 MOUNTING OF GUN MUZZLE DEVICES Frank A. Pachmayr, Culver City, and Walter R. Nass, Escondido, Calif., assignors to Firearm Accessories, Inc., Los Angeles, Calif., a corporation of California Filed July 10, 1962, Ser. No. 208,732 19 Claims. (Cl. 269--45) This invention relates to improved apparatus for mounting a muzzle device, such as a shot gun choke, on the forward end of a gun barrel.

The attachment of a choke device or the like to a gun barrel alters the aiming characteristics of the gun in a manner requiring compensation for this change. For one thing, the muzzle attachment normally reduces the recoil of the gun, and because of this reduction in recoil tends to cause the gun to hit a target slightly lower than if no muzzle device were present. Further, since the muzzle device is of a diameter somewhat larger than the rest of the barrel, the application of the attachment to the barrel usually requires elevation of the forward sight of the gun, and for this reason also the gun may hit a target slightly low with respect to the sighting line.

To compensate for the 'above discussed tendency of a gun having a muzzle attachment to shoot low, it has been found desirable to mount such muzzle attachments in positions of slight angularity with respect to the main axis of the gun barrel. More particularly, the muzzle attachment is so mounted as to be aimed slightly upwardly, preferably at an angle between about degrees and 1 /2 degrees. The general object of the present invention is to provide apparatus for thus mounting a United States Patent 0 3,257,108 Patented June 21, 1966 form of a longitudinally slit radially expansible sleeve, adapted to be expanded by a suitable cam type axially movable mandrel. In another form of the invention, the expansible unit may bean elastomeric ring adapted to expand radially upon the application of axial compressive forces thereto. It is also contemplated that the locating structure for engaging the rear end of the barrel may have portions of several different diameters, for engaging and locating any of several different sizes of gun barrels.

The above and other features and objects of the present invention will be better understood from the following detailed description of the typical embodiment illus- FIG. 3 is an enlarged fragmentary representation of the apparatus of FIG. 1;

muzzle attachment at a predetermined very accurately I measurable slight upward angle with respect to a gun barrel, to effect the desired compensation for the change in aiming characteristics of the gun resulting from the application of the muzzle attachment to the barrel. In a device embodying the invention, the muzzle attachment and gun barrel are firmly held in the desired positions of relative angularity, while a rigid connection is made between the two units. This connection may be effected in any desired manner, but for maximum simplicity is preferably attained by merely applying a strong bonding cc ment, such as an epoxy cement, to the attachment and gun barrel, and allowing this cement to dry to a hardened condition while the attachment is held in the proper position of angularity with respect to the gun barrel.

Certain specific features of novelty have to do with the preferred mounting of the unit which holds the muzzle attachment in a manner such that this unit is shiftable between two or more positions of different angularity, in order that the attachment may be connected to a gun barrel in any of various dilferent settings. Preferably, the unit for holding themuzzle attachment is mounted for pivotal movement between these diiferent settings, and may be rigidly locked in any desired setting. For locking the unit in its ditferent positions, I may utilize one or more screws, pins or other locking elements adapted to fit into mating apertures within the attachment holding unit and a coacting mounting structure, and serving to secure the unit in different settings when the locking element. is received within the different sets of apertures. The rear end of the gun barrel may be accurately located by engagement with a positioning structure, which may consist of a part projecting into and closely interfitting with the rear end of the barrel. For effecting tight engagement of this locating structure with the gun barrel, I may form the structure to be expansible radially outwardly into tight gripping engagement with the inner surface of the barrel. In certain forms of the invention, the eX-pansible unit takes the FIG. 4 is a fragmentary view taken on line 44 of FIG. 3;

FIG. 5 is a fragmentary vertical section taken on line 55 of FIG. 3;

FIG. 6 is a vertical section taken on line 66 of FIG. 3;

FIG. 7 is a greatly enlarged fragmentary section taken on the generally vertical arcuate line designated 77 in FIG. 3;

FIGS. 8, 9, 10 and 11 represent four variational types of devices for holding the rear or chamber end of the gun barrel in the present apparatus;

FIG. 12 is a'view similar to a portion of FIG. 6, showing a different form of muzzle device holder; and

FIG. 13 is a section taken on line 1313 of FIG. 12;

Referring first to FIG. 1, I have represented at 10 a conventional gun barrel, to which there is to be applied a muzzle attachment 11. The attachment and barrel are secured in desired positions of slight angularity with respect to one another by means of a device 12 constructed in accordance with the invention, and typically mounted on a table or other support surface represented at 13. The apparatus 12 includes a base rail or mounting part 14, a unit 15 for receiving and holding the muzzle attachment 11, and a second unit 16 for engaging and locating the rear end of the gun barrel 10.

While it is to be understood that any of numerous different types of muzzle attachments may be connected to a gun barrel by the apparatus of the invention, there is typically illustrated in FIG. 2 one form of muzzle device which may be used, this device being shown for the purpose of representing broadly the manner in which the muzzle device may bereceived about the front of the gun barrel. In the FIG. 2 arrangement, the muzzle device 11 consists of a main tubular body 17, to the rear portion of which there is threadedly connected a securing ring 18, for retaining the choke device in a fixed axial position relative to a ring 19 received within an annular groove 20 formed in the end portion of gun barrel 10. Ring 19 may be formed of two semicircular sections, and may have the externally rounded cross-section illustrated in FIG. 2, for engagement at opposite axial sides by correspondingly curved annular surfaces 21 and 22 of parts 17 and 18.

At locations forwardly of and rearwardly of ring 19, the external surface of barrel 10 has a slight clearance (at 23 and 24) from the inner surfaces of parts 17 :and 18, to allow for slight universal adjusting movement of muzzle device 11 relative to barrel 10 about a center 25 lying on the axis 26 of barrel 10. To facilitate such limited adjusting movement of the muzzle device, the curved surfaces 21 and 22 of parts 17 and 18, and the engaged external surface of ring 19, may all be of spherical curvature, about the discussed center 25. The clearance spaces 23 and 24 are of suflicient size to allow adjustment of the muzzle device to a position in which the axis 26' of the muzzle de vice is disposed at the proper angle with respect to barrel axis 26 to effect the compensation which is required as a result of the presence of the muzzle device on the barrel. The usual forward sight 27 is of course mounted on the muzzle device, for coaction with the rear sight 28 on the rear portion of the barrel, in aiming the gun. At its forward end, the part 17 of the muzzle device may carry a choke tube typically represented at 29, for controlling the pattern of the shot fired by the gun, with tube 29 being suitably secured to part 17, as by a threaded connection at 30.

The rail or mounting member 14 may take the form of a horizontally elongated rigid metal I beam, having the cross-section represented in FIG. 6. More particularly, this member 14 may have a vertical web portion 31, formed integrally with a bottom horizontal planar cross piece or flange 32, and a top horizontal planar cross piece or flange 33. Bottom flange 32 may be rigidly secured to the supporting table or structure 13, as by bolts represented at 34 in FIG. 6, while the units and 16 are mounted to upper flange or plate 33.

Referring now to FIGS. 3, 4 and 6, the unit 15 for holding muzzle attachment 11 may include a first bracket section 35, having a horizontal bottom flange 36 which is secured by bolts 37 to the upper side of top plate 33 of part 14. At one of the edges of bottom flange 36, part 35 has an integral upstanding flange 33, whose inner and outer parallel surfaces 39 and 4t lie in vertical planes which extend parallel to, but are offset laterally from, the vertical plane of central web 31 of rail 14. Adjacent the inner surface 39 of flange 38, there is mounted a block or section 41 containing a cylindrical passage 42 of a normal diameter which is only slightly larger than the diameter of the outer cylindrical surface of the muzzle attachment, to receive and effectively locate the attachment within block 41. An axially extending groove 127 is provided in the undersurface of the top portion of block 41, of a width to exactly receive and closely confine forward sight 27 or" the muzzle device, and thereby locate the sight in a precisely upwardly pointing position. At the side of block 41 which faces away from flange 38, the material of this block may be interrupted by a horizontal slit or gap 43, with the vertical height of this gap being variable by means of a screw 44, to tighten the wall of passage 42 against and about the muzzle device. Screw 44 has an upper head bearing downwardly against the top surface of block 41, and extends downwardly through an un-' threaded bore 45 in the upper part of block 41, with the screw 44 within bore 46 causes the upper head of thescrew to pull downwardly on the upper portion of block 41, and reduce the height of gap 43, thereby restricting passage 42 to a diameter corresponding to the outside diameter of the muzzle attachment. Block 41 may be formed of a material, such as metal, which is essentially rigid, but has a capacity for some resilient deformability, between a normal condition in which passage 42 has a diameter slightly greater than the outside diameter of the muzzle attachment, to easily receive that attachment, and a reduced diameter condition in which the passage 42 is at least as small as the outside diameter of the muzzle attachment, and tightly grips that attachment. The axis of passage 42 is designated 47, and of course coincides with axis 26' of the muzzle attachment when the attachment is received within passage 42. Block 41 has, adjacent surface 39, a Vertical flange portion 48, and has a vertical planar side surface 49 abutting against and slidably engaging surface 39 of flange 38. Surface 49 is retained in abutting engagement with surface 39 by means of a pivot screw 50, whose end portion 51 is threadedly connected into block 41 (FIG. 4), and whose enlarged head 52 abuts against the outer side flange 38. Cylindrical portion 53 of screw 50 is journalled within a correspondingly dimensioned cylindrical bore 54 formed in flange 38, to mount block 41 and its integral flange portion 48 for pivotal movement relative to flange 38 about a horizontal axis 55 extending perpendicular to

vertical surfaces

39 and 49, and extending perpendicular to and intersecting axis 47 of passage 42. The threaded portion 51 of screw 50 is a sufliciently tight fit within the coacting threaded opening in part 41 to retain the screw in fixed relation relative to part 41, and the engagement of head 50 with the outer side of flange 38 is sufliciently loose to allow the discussed pivotal movement of part 41, while still retaining

surfaces

39 and 40 at all times in abutting engagement. Also, a second screw 153 may be threaded into wall 48 and extended through and be movable within an arcuate slot 154 in flange 38, and have a head slidably engaging this flange to assist screw 53 in holding flanges 33 and 48 together.

Flange portion 48 of part 41 contains a number of threaded openings 56 through 62 (typically. six such openings), whose axes may extend parallel to axis 55, and which may typically the arranged along two arcuate lines 164 and centered about axis 55. For coaction with these openings 56 through 62, the flange portion 38 of part 35 has cylindrical bores 63 which may also be located along the same two

arcuate lines

164 and 165 with respect to axis 55, and which are spaced approximately in correspondence with the different apertures 56 through 62. The axes 64 of openings 63, like the axes of the threaded openings 56 through 62, are parallel to pivotal axis 55. For locking the block 41 in any desired pivotal position, there is provided a lock element 65 (FIG. 7), having a threaded portion 66 engageable within any of the different threaded openings 56 through 62, and having a reduced diameter cylindrical portion 67 of a size corresponding to bores 63, and receivable therein. Thus, when the pin or element 65 is received within any one of the threaded openings 56 through 62, and projects into the corresponding bore 63, the pin 65 acts to securely lock block 41 in a corresponding predetermined position of angularity with respect to the later to be discussed horizontal axis 68 of barrel holding unit 16. This axis 68 with which axis 26 (FIG. 2) of the gun barrel'coincides when the latter is held in the apparatus, intersects the previously mentioned axis 47 of passage 42 (axis 26' of the muzzle device) at the location of transverse pivotal axis 55 (and axis 25 of FIG. 2).

The various bores 63 are spaced apart slightly differently than are the various threaded openings '56 through 62, in a relation such that, in any one setting of block 42, pin 65 is receivable in locking relation within only one of the threaded openings and the associated opening 63. When the pin is received within the first threaded opening 56, and the associated aperture 63, this may typically serve to lock block 41 in a position in which its axis 47 coincides exactly with barrel axis 68, so that the muzzle device is exactly aligned with the barrel. When the locking pin is received within opening 57, muzzle device axis 47 may be disposed at an upward angle of one-fourth of a degree relative to axis 68 of the barrel. Similarly, upward inclinations of one-half degree, three-quarters degree, one degree, one and onefourth degree and one and one-half degree may be attained by connection of locking pin 65 into threaded

openings

58, 59, 66, 61 and 62 respectively. For indicating the setting of block 41, the flange portion 48 of block 41 may have an arcuate edge 168 having markings 69 coacting with marking 78 on an arcuate' edge of a portion 171 of flange 38. In any of the various settings of block 41, only one of the markings 69 will exactly coincide with one of the markings 70, with the angularity being indicated in degrees adjacent that pair or" coinciding markings.

The unit 16 for engaging and locating the rear or chambetween its different settings.

ber end of barrel may include a rigid typically level body member 71, which may have the essentially triangular cross-section represented in FIG. 5. The undersurface 72 (FIG. '5) of body part 71 may be planar, and slidably engage the upper surface of top flange 33 of part 14. At opposite sides of flange 33, body part 71 may have two spaced

parallel depending flanges

73 and 74, to confine flange 33 between these

flanges

73 and 74 in a manner allowing shifting movement of part 71 along the upper surface of flange 33 only in a direction parallel to barrel axis 68. The flange 74 may carry a pin 75 engageable with the undersurface of flange 33 to hold one side of body 71 against upward movement from flange 33. At the opposite side of flange 33, depending flange 73, may carry a locking screw 76, which is threadedly connected at 77 into flange 73, and which has a tapered end portion 78 adapted to be tightened inwardly against the underside of flange 33 in a manner frictionally locking block 71 in any desired setting relative to member 14. Screw 76 may have a knurled knob 79 for facilitating the tightening and loosening of the set screw.

At its side which faces toward the muzzle .attachment holding unit 15, block 71 has a vertical planar surface 80, disposed transversely of axis 68. there is mounted a barrel locating part 81, having a flat surface 82 engaging surface 80, and having a locating pin 83 received within a coacting recess in block 71 to locate part 81 relative to block 71. The element 81 forms a tubular sleeve 84 projecting toward unit 15, and centered about axis 68. Sleeve 84 has a series of circularly spaced parallel longitudinally or axially extending slits 85, and is formed of a resilient material (such as spring steel) allowing outward expansion of the sleeve to an increased diameter for gripping the inner surface of barrel 10. The free end of sleeve 84 is expansible outwardly in this manner by means of an expanding mandrel 86, having a conical tapering surface 87 engaging the inner side of the free end of the sleeve, and acting to expand the sleeve outwardly in response torightward movement of mandrel 86 (as viewed in FIG. 3) along axis 68. Between sleeve portion 84 of part 81, and surface 80, the part 81 may externally have a tapering conical surface 88 and a short cylindrical surface 89.

For actuation of mandrel 86 axially, this part may be rigidly carried by a reduced diameter stem 90, which extends through and is slidable within a bore 91 formed within block 71, and which has an end portion 92 pivotally connected to a cam actuating lever 93 by a pin 94. As will be apparent, the lever 93 has a camming portion 95, which may be bifurcated to engage a pressure plate 96 at both sides of stem 90, with element 95 having camrning surfaces 97 at both of these sides whose radius with respect to the pivotal axis varies in a manner such that actuation of lever 93 bet-ween the full line position of FIG. 1 and the broken line position of that figure acts to pull mandrel 86 to the right, as viewed in-FIG. 3, and to thereby expand sleeve 84 outwardly into tight essentially annular gripping engagement with the inner wall of the rear end portion of barrel 10. For assisting in properly locating sight 28 of the gun barrel 10 in a directly upwardly facing position, box 71 may carry an indicator or indexing element 98 (FIGS. 3 and 4), having a pointer end 99 which should directly overlie and'directly align with sight 28 when barrel 10 is turned to a properly oriented position. Element 98 may be mounted for sliding movement parallel to axis 68, by mounting element 98 slidably within a dovetail shaped recess or groove 100 in the upper surface of block 71, with the sliding movement of part 98 typically being limited by means of a screw 101 whose head engages the upper side of part 98 and whose shank extends downwardly through an elongated slot 102 in part 98 and is connected threadedly into block 71. A handle 103 may be formed on part 98, for actuating it To now describe the complete process of ,securing a Against this surface,

6 muzzle attachment to a gun barrel utilizing the apparatus of FIGS. 1 through 7, assume that it is desired to mount the choke device 11 of FIG. 2 on shotgun barrel 10, with the axis 26' along which shot is directed by choke 11 be ing disposed at a slight angle of one and one-fourth degrees relative to axis 26 of the shotgun barrel. In this case, block 41 is pivoted about axis 55 to the position represented in FIG. 3, in which locking pin 65 may be, and is, screwed into threaded opening 61, with the unthreaded end portion 67 of the lock pin being received within the corresponding aperture 63 in flange 38, to positively lock block 41 in the one and one-fourth degree setting. This setting is indicated by the fact that the two markings opposite the number one and one-fourth coincide, whereas the other markings 69 and 70 do not coincide.

Next, the operator may insert muzzle device 11 into passage 42 of block 41, with the outer cylindrical surface of the muzzle device being engaged and centered by the wall of passage 42, and with pivotal axis 25 of the muzzle device (-FIG. 2) coinciding with pivotal axis 55 of block 41, and axis 26 of the muzzle device (which is also the center about which the external cylindrical surface of the muzzle device is formed) coinciding with axis 47 of passage 42. Sight 27 on the muzzle device is received within slot 127 in the upper portion of block 41, to retain the sight in a proper upwardly directed setting. Screw 44 may then be tightened, to securely clamp the muzzle device in a properly centered and oriented position within block 41, so that the device is very accurately located in the desired one and one-half degree angular position relative to axis 68.

The barrel 10 may be inserted into the muzzle device either prior to or after attachment of the muzzle device into block 41. Rings 18 and 19 are secured in the positions of FIG. 2, to attach the muzzle device and barrel together, and a suitable bonding cement, preferably a very hard setting epoxy resin, may be applied to the inner surfaces of parts 17, 1-8 and 19, and the external surfaces of parts 10 and 19, preferably filling the annular clearance spaces 23 and 24, so that as soon as the cement has set, the muzzle device will be rigidly and permanently retained in the proper slightly angular position relative to the barrel.

Before the epoxy resin or other cement has had an opportunity to set, the operator slides block 71 forwardly (to the left in FIG. 3) far enough to cause sleeve 84 to extend into the chamber end of barrel 10, as to the FIG. 3 setting, following which the barrel may be turned if necessary to properly align sight 28 with index element 98 in a manner locating the sight portion of the barrel at exactly the proper upwardly directed position. The operator locks block 71 in position by means of screw 76, and then may swing lever 93 downwardly from the full line position of FIG. 1 to the broken line FIG. 1 position, to expand sleeve 84 outwardly against the barrel and locate it precisely relative to block 71. The cement is then hardened while the apparatus holds the muzzle attachment and barrel in the discussed slightly angular relative positions. If desired, the cement may be an air-drying type of bonding compound, but preferably it is a thermosetting resin (such as the previously mentioned epoxy resin), which is cured by baking the resin for. an appropriate period, say for example for a period'of two hours at 250 Fahrenheit, in the case of an epoxy resin. If necessary, the entire mounting rail 14 and all of the carried parts may be bodily transported into a curing oven during the resin curing period. After the resin is set, the barrel and muzzle attachment may be removed from the apparatus and the installation process is complete.

FIG. 8 illustrates a variational form of the invention, which may be considered asidentical with that of FIGS. 1 through 7 except as to the manner of construction of the barrel gripping expansible sleeve or collet 84a, and the coacting parts. In this arrangement, the sleeve has a first set of circularly spaced slits aextending into the material of the sleeve from one of its ends, and has a second set of slits 185a extending into the material of the sleeve from its opposite end, so that both ends of the sleeve may be expanded radially against the resilience of the sleeve material. Mandrel 86a is actuable rightwardly in the same manner as mandrel 86 of FIG. 3, to expand the 'left end of the sleeve, while the right end of the sleeve is simultaneously engaged by a correspondingly tapering frustro-conical projection 88a formed on a part 81a corresponding to part 81 of FIG. 3. Thus, instead of the right end of the sleeve being rigidly attached to part 81a, in correspondence with the FIG. 3 arrangement, this right end of the sleeve engages tapered surface 88a, and is expansible radially by that surface upon rightward actuation of the mandrel. If desired, the ends of the sleeve may have tapered surfaces shaped in cor-respondence with the engaged tapered surfaces of parts 86a and 81a, to facilitate the camming action. The FIG. 8 arrangement acts to locate the right end of the gun barrel somewhat more effectively than in FIG. 3, by virtue of the fact that the sleeve 84a tends to expand uniformly along its entire length, rather than only a one end.

FIG. 9 shows an arrangement in which there is substituted for the part 81 of FIG. 3 a rigid element 81b, which may be rigidly retained within a block 71b (corresponding to block 71 of FIG. 3) by a set screw represented at 83b. Part 81b may have a series of externally

cylindrical portions

104, 105, 106, 107, 108 and 109, all centered about an axis 68b corresponding to axis 68 of FIG. 3, and of different diameters corresponding to the internal diameters of the rear portions of a series of different sizes of gun barrels. When using this arrangement, the block 71b is merely actuated to the left far enough to move the appropriate one of the

cylindrical portions

104, 105, 106, 107, 108 or 109 into engagement with the inner surface of the rear end portion of the gun barrel, to locate the barrel in properly centered position about axis 68b.

In the FIG. 10 arrangement, there is provided a resiliently expanasible sleeve or collet 840, corresponding to sleeve 84d of FIG. 8, except that the sleeve has a series of

portions

110, 111, 112, 113 and 114 which are externally cylindrical and of progressively increasing diameter, all being centered about the main axis 68c of the device, for engaging and gripping different sizes of gun barrels (as discussed in connection with FIG. 9). The expanding mandrel 86c engages the reduced diameter end of collet 84c, while the opposite end is engageable with a frustroconical surface 880 on a part 81c corresponding to parts 81 and 81a of FIGS. 3 and 8 respectively. As in FIG. 8, sleeve 840 has two sets of longitudinal slits 85c and 185s extending into the material of the sleeve from opposite ends thereof, and alternating about the circular extent of the sleeve. The

surfaces

115 and 116 which engage cam surfaces 880 and 188c may be tapered in correspondence with the engaged cam surfaces. In using the FIG. 10 device, the sleeve 840 is first inserted into the gun barrel to a position in which the proper one of the surfaces 110, 111, etc. is received within and substantially engages the inner end portion of the barrel, following which element 860 is actuated to the right, as viewed in FIG. 10, to expand the sleeve 84c outwardly into tight gripping engagement with the barrel. Since slits 85c and 1850 extend into the sleeve from its opposite ends, and extend along almost the entire length of the sleeve, the sleeve expands radially along substantially its entire length upon actuation of mandrel 86a.

FIG. 11 represents another form of the invention, in which there is substituted for the sleeve 84 of FIG. 3, a disk or ring 84d of rubber or other elastomeric material, which may normally be slightly undersized with respect to the particular size of barrel 10d with which the device is to be used, but which disk 840. is adapted to be expanded against its own resilience radially outwardly into tight gripping engagement with the inner surface of the gun barrel. For effecting such expansion, the right side to part 81 of FIG. 3, and mounted on the face of a block 71d corresponding to part 71 of FIG. 3. The opposite side of disk or ring 84d may be engaged by a member 86d which is carried by a stem W0. adapted to be actuated to the right by a cam lever such as that shown at 93 in the first form of the invention. The surface of part 860! which engages element 84d may be convexly curved, as represented at 186d, to maximize the extent to which element 84d is expanded outwardly upon right-ward movement of element 86d relative to part 81d. The broken lines at the periphery of element 84d in FIG. 11 represent the position to which this part is expanded upon rightward actuation of parts 86d. As will be apparent, the part 84d may have a central opening through :which stern 911d extends, to allow projection of that stem to a position for connection to an actuating lever.

FIGS. 12 and 13 represent a slightly altered form of muzzle device holder 41a, which may be used in connection with different sizes of adapter rings 141 for adapting the holder to receive muzzle devices of different gauges. Specifically, each adapter 141 may take the form of a sleeve which is received within body 41e and is keyed in position by reception of a pin 142, carried at the forward end of body 412, Within an axial slit 143 in the sleeve. This slit also enables sleeve 141 to constrict and expand with body 412. The reduced caliber muzzle device 116 is positioned within sleeve 141 behind pin 142, with sight 27a projecting upwardly through slit 14-3 and into recess 12%. Any number of adapters of different internal diameters may of course be provided for use with different muzzle devices, or the holder 41e may be used without any adapter for maximum size muzzle devices.

We claim:

1. Apparatus for holding a gun muzzle attachment and a gun barrel having a muzzle end and a firing chamber end while said attachment is being secured to the barrel, said apparatus including a support, a first fixture mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said second fixture being constructed to hold said attachment in almost exact axial alignment with the muzzle end of a barrel held by said first fixture but at a predetermined very slight upward angle relative thereto as the barrel and attachment are secured together, to compensate for the presence of the muzzle attachment in aiming, there being means for indicating precisely when said second fixture and attachment are at said predetermined very slight angle to the muzzle end of the barrel.

2. Apparatus for holding a gun muzzle attachment and 'a gun barrel having a muzzle end and a firing chamber end while said attachment is being secured to the barrel, said apparatus including a support, a first fixture mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gun bar-rel, and a second fixture mounted to said support for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said first fixture including a projection projecting essentially toward said second fixture and constructed to extend into and fit closely within and thereby position said firing chamber end of the barrel, said second fixture being constructed to hold said attachment in almost exact axial alignment with a barrel held by said first fixture but at a predetermined very slight upward angle relative thereto as the barrel and attachment are secured together, to compensate for the presence of the muzzle attachment in aiming.

3. Apparatus for holding a gun muzzle attachment and a gun barrel having a muzzle end and a firing chamber end while said attachment is being secured to the barrel, said apparatus including a support, a first fixture mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said first fixture including an expansible projection projecting essentially toward said second fixture and constructed to extend into and expand radially outwardly into tight gripping engagement with and thereby position said firing chamber end of the barrel.

4. Apparatus -for holding a gun muzzle attachment and a gun barrel having a muzzle end and a firing chamber end While said attachment is being secured to the barrel, said apparatus including a support, a first fixture mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support for holding and accurately positioning said muzzle attachment at said muzzle end of'the barrel, said second fixture being constnucted to hold said attachment in almost exact axial alignment with a barrel held by said first fixture but at a predetermined very slight upward angle relative thereto as the barrel 'and attachment are secured together, to compensate for the presence of the muzzle attachmentin aiming, said first fixture including a sleeve projecting essentially toward said second fixture and adapted to project into and fit closely within and thereby position said firing'chamber end of the barrel, an axially movable mandrel for expanding said sleeve, and means tor actuating said mandrel axially.

5. Apparatus for holding a gun muzzle attachment and a gun barrel having a muzzle end and a firing chamber end while said attachment is being secured to the barrel, said apparatus including a support, a first fixture mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gunbar-rel, and a second fixture mounted to said support for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said second fixture being constructed to hold said attachment in almost exact axial alignment with a barrel held by said first fixture but at a predetermined very slight upward angle relative thereto as the barrel and attachment are secured together, to compensate for the presence or" the muzzle attachment in aiming, said first fixture including a sleeve projecting essentially toward said second fixture and adapted to project'into and fit closely within and thereby position said firing chamber end of the barrel, an axially movable mandrel for expanding said sleeve, a swinging lever having a cam portion operable to shift said mandrel axially in a sleeve expanding direction upon swinging movement of said lever, and means mounting said lever for swinging movement.

6. Apparatus for holding a gun muzzle attachment and a gun barrel having a muzzle end and a firing chamber end while said attachment is being secured to the barrel,

said apparatus including a support, a first fixture mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, a second fixture mounted to said support for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said second fixture being constructed to hold said attachment in almost exact axial alignment with the muzzle end of a barrel held by said first fixture but at a predetermined very slight upward angle relative thereto as the barrel and attachment are securedtogether, to compensate for the presence of the muzzle attachment in aiming, a mounting structure mounting said second fixture for movement between a plurality of positions for holding said attachment at a plurality of different very slight angles with respect to the muzzle end of said barrel, and means for indicating precisely when said second fixture and attachment are at said different very slight angles to the barrel.

7. Apparatus for holding a gun muzzle attachment and a gun barrel having a muzzle end and a firing chamber end-while said attachment is being secured to the barrel, said apparatus including a support, a first fixture .mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said second fixture being constructed to hold said attachment in almost exact axial alignment with a barrel heldby said first fixture but at a predetermined very slight upward angle relative thereto as the barrel and attachment are secured together, to compensate for the presence of the muzzle attachment in aiming, there being means for indicating precisely when said second fixture and attachment are at said predetermined very slight angle to the barrel, said second fixture including a structure containing a recess for receiving said attachment and opening essentially toward said first fixture and being tightenable radially inwardly against said attachment, and means for releasably tightening said structure against said attachment.

. 8. Apparatus for holding a gun muzzle attachment and a gun barrel having a muzzle end and a firing chamber end while said attachment is being secured to the barrel, said apparatus including a support, a first fixture mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support for holding and accurately positioning said muzzle at- I tachment at said muzzle end of the barrel, said second fixture being constructed to hold said attachment in almost exact axial alignment with a barrel held by said first fixture but at a predetermined very slight upward angle relative thereto as the barrel and attachment are secured together, to compensate for the presence of the 'muzzle attachment in aiming, there being means for indiend while said attachment is being secured to the barrel said apparatus including a support, a first fixture mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said first fixture including a projection projecting essentially toward said second fixture and constructed to extend into and fit,

closely within and thereby position said firing chamber end of the barrel, said second fixture being constructed 7 to hold said attachment in almost exact axial alignment with a barrel held by said first fixture but at predetermined very slight upward angle relative thereto as the barrel and attachment are secured together, to compensate for the presence of the muzzle attachment in aiming, said projection having different axially aligned portions of a plurality of different diameters for selectively engaging and fitting closely within and thereby accurately locating barrels of different diameters.

10. Apparatus for holding a gun muzzle attachment and a gun barrel having a muzzle end and a firing chamber end while said attachment is being secured to the barrel, said apparatus including a support, a first fixture mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said second fixture being constructed to hold said attachment in almost exact axial alignment with a barrel held by said first fixture but at a predetermined very slight upward angle relative thereto as the barrel and attachment are secured together, to compensate for the present of the muzzle attachment in aiming, there being means for indicating precisely when said second fixture and attachment are at said predetermined very slight angle to the barrel, said first fixture having an indicator element positioned to indicate when the barrel has been turned about its axis to a predetermined proper setting with respect to said first fixture.

11. Apparatus for holding a gun muzzle attachment and a gun barrel having a muzzle end and a firing chamber end while said attachment is being secured to the barrel, said apparatus including a support, a first fixture mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, a second fixture mounted to said support and for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said second fixture being constructed to hold said attachment in almost exact axial alignment with a barrel held by said first fixture but at a predetermined very slight upward angle relative thereto as the barrel and attachment are secured together, to compensate for the presence of I the muzzle attachment in aiming, there being means for ber end while said attachment is being secured to the barrel, said apparatus including a first fixture constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, a second fixture for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said first fixture including a projection projecting essentially toward said second fixture and constructed to extend into and fit closely within and thereby position said firing chamber end of the barrel, said second fixture being constructed to hold said attachment in almost exact axial alignment with a barrel held by said first fixture but at a predetermined very slight upward angle relative thereto as the barrel and attachment are secured together, to compensate for the presence of the muzzle attachment in aiming, said second fixture containing a recess for receiving said attachment and opening toward said projection and being tightenable, against said attachment, a support carrying both of said fixtures, and means mounting one of said fixtures to said support for a movement relatively toward and away from the other.

13. Apparatus for holding a muzzle attachment and a gun barrel having a muzzle end and a firing chamber end While said attachment is being secured to the barrel, said apparatus including an elongated support, a first fixture mounted to said support toward a first end thereof and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support toward a second end thereof for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said first fixture including a projection projecting essentially toward said second fixture and constructed to extend into and be expanded tightly against and thereby accurately position said firing chamber end of the barrel, means for expanding said projection against the barrel, said second fixture containing a passage for receiving said attachment and opening toward said projection and being tightenable radially inwardly against the attachment, means for tightening said second fixture, a pivotal connection mounting said second fixture for slight pivotal movement relative to said support and said first fixture between a plurality of different positions in which said passage and an attachment therein are disposed in almost exact alignment with said projection and a barrel held thereby but at a plurality of different predetermined very slight upward angles, in the order of 0 to 2 degrees, relative thereto, and means for securing said second fixture in said different angular positions.

14. Apparatus for holding a muzzle attachment and a gun barrel having a muzzle end and a firing chamber end while said attachment is being secured to the barrel, said apparatus including an elongated support, a first fixture mounted to said support toward a first end thereof and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support toward a second end thereof for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said first fixture including a projection projecting essentially toward said second fixture and constructed to extend into and be expanded tightly against and thereby accurately position said firing chamber end of the barrel, an axially movable mandrel in said projection operable by axial movement to expand said projection, a swinging lever having a cam portion for actuating said mandrel axially, said second fixture containing a passage for receiving said attachment and opening toward said projection and being tightenable radially inwardly against the attachment, means for tightening said second fixture, a pivotal connection mounting said second fixture for slight pivotal movement relative to said support and said first fixture between a plurality of different positions in which said passage and an attachment therein are disposed in almost exact alignment with said projection and a barrel held thereby but at a plurality of different predetermined very slight upward angles, in the order of 0 to 2 degrees relative thereto, means for securing said second fixture in said different angular positions, means mounting one of said fixtures for movement along said support toward and away from the other fixture and to a plurality of different positions, and means for securing said one fixture in any of said different positions.

15. Apparatus for holding a muzzle attachment and a gun barrel having a muzzle end and a firing chamber end while said attachment is being secured to the barrel, said apparatus including an elongated support, a mounting part carried by said support, a first fixture mounted to said mounting part and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support toward a second end thereof for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said first fixture including a projection carried by said mounting part and projecting essentially toward said second fixture and having an externally essentially arcuately curved surface constructed to extend into and be expanded tightly against and thereby accurately position said firing chamber end of the barrel, an axially movable mandrel mounted to said mounting part for axial movement relative thereto and operable to expand said projection by said axial movement, a lever mounted to said mounting part for swinging movement and connected to said mandrel to actuate it, a cam carried by said lever and exerting force against said mounting part toward said second fixture in a relation to actuate the mandrel axially, said second fixture containing a passage for receiving said attachment and opening toward said projection and being tightenable radially inwardly against the attachment, means for tightening said second fixture, a pivotal connection mounting said second fixture for slight pivotal movement relative to said support and said first fixture between a plurality of different positions in which said passage and an attachment therein are disposed in almost exact alignment with said projection and a barrel held thereby but at a plurality of different predetermined very slight upward angles, in the order of to 2 degrees, relative thereto, means for securing said second fixture in said different angular positions, and a sliding connection mounting said mounting part for sliding movement toward and away from said second fixture and including means for securing said mounting part in different positions along said support.

16. Apparatus for holding a muzzle attachment of a gun barrel having a muzzle end and a firing chamber end While said attachment is being secured to the barrel, and apparatus including an elongated support, a mounting part carried by said support, a first fixture mounted to said mounting part and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support toward a second end thereof for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said first fixture including a projection in the form of an axially split expansible sleeve carried by said mounting part and projecting essentially toward said second fixture and having an externally essentially arcuately curved surface constructed to extend into and be expanded tightly against and thereby accurately position said firing chamber end of the barrel, an axially movable mandrel mounted to said mounting part for axial movement relative thereto and operable to expand said projection by said axial movement, to a lever mounted to said mounting part for swinging movement and connected to said mandrel to actuate it, a cam carried by said lever and exerting force against said mounting part toward said second fixture in a relation to actuate the mandrel axially, said second fixture containing a passage for receiving said attachment and opening toward said projection and being tightenable radially inwardly against the attachment, a screw for tightening said second fixture, a carrier part mountedto said support and movably carrying said second fixture, a pivotal connection mounting said second fixture to said carrier part for slight pivotal movement relative to said carrier part and said support and said first fixture between a plurality of different positions in which said passage and an attachment therein are disposed in almost exact alignment with said projection and a barrel held thereby but at a plurality of different predetermined very slight upward angles, in the order of 0 to 2 degrees, relative thereto, said carrier part and said second fixture containing a plurality of sets of apertures adopted to register in said different pivotal positions of the second fixture, threaded pin means receivable within said registering apertures to releasably lock said second fixture in said different positions, and a sliding connection mounting said mounting part for sliding movement toward and away from said second fixture and including means for securing said mounting part in different positions along said support.

17. Apparatus for holding a gun muzzle attachment and a gun barrel having a muzzle end and a firing chamber end While said attachment is being secured to the barrel, said apparatus including a support, a first fixture mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said second fixture being constructed to hold said attachment in almost exact axial alignment with a barrel held by said first fixture but at a predetermined very slight upward angle relative thereto as the barrel and attachment are secured together, to compensate for the presence of the muzzle attachment in aiming, said second fixture containing a passage for receiving said attachment and being tightenable radially inwardly against the attachment, and said second fixture containing a localized recess extending radially outwardly thereinto from said passage at the upper side thereof and adapted to receive a sight on the attachment to properly locate the sight relative to said barrel.

18. Apparatus for holding a gun muzzle attachment and a gun barrel having a muzzle end and a firing chamber end while said attachment is being secure to the barrel, said apparatus including a support, a first fixture mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said second fixture being constructed to hold said attachment in almost exact axial alignment with a barrel held by said first fixture but at a predetermined very slight upward angle relative thereto as the barrel and attachment are secured together, to compensate for the presence of the muzzle attachment in aiming, there being an indicator device on said first fixture for indicating the proper rotary positioning of the barrel, and means mounting said indicator device for shifting movement relative to the fixture between active and retracted positions.

19. Apparatus for holding a gun muzzle attachment and a gun barrel having a muzzle end and a firing chamber end while said attachment is being secured to the barrel, said apparatus including a support a first fixture mounted to said support and constructed and positioned to engage and accurately locate said firing chamber end of the gun barrel, and a second fixture mounted to said support for holding and accurately positioning said muzzle attachment at said muzzle end of the barrel, said second fixture being constructed to hold said attachment in almsot exact axial alignment with a barrel held by said first fixture but at a predetermined very slight upward angle relative thereto as the barrel and attachment are secured together, to compensate for the presence of the muzzle attachment in aiming, said second fixture containing a passage for receiving said attachment and being tightenable radially inwardly against the attachment, said second fixture containing a localized recess extending radially outwardly thereinto from said passage at the upper side thereof and adapted to receive a sight on the attachment to properly locate the sight relative to said barrel, and there being a sleeve removably receivable in the said passage to adapt the second fixture for different size muzzle attachments and containing an opening for passing said sight of an attachment therethrough into said localized recess, and interfitting keying means on said second fixture and said sleeve for retaining the latter in a predetermined proper rotary orientation.

References Cited by 'the Examiner UNITED STATES PATENTS 402,108 4/1889 Ries. 1,368,683 2/1921 Anderson 269- 2,226,078 12/1940 Spahn 113103 X 2,227,443 1/ 1941 Denner 269 -5 2 2,497,943 2/ 1950 Ingwer 26969 2,662,266 12/1953 Powell et al 29--1.1 2,731,712 1/ 1956 Laux 269-82 X 2,767,676 10/1956 Johnson et a1. 113103 2,767,677 10/1956 Johnson et a1 269--52 X 2,853,771 9/1958 Melville 113102 X 2,853,773 9/1958 Darasko 113103 X FOREIGN PATENTS 952,484 11/ 6 Germany.

RQBERT C. RIORDON, Primary Examiner. BROUGHTON G. DURHAM, Examiner.

T. E. BEALL, JR., F. I. POWERS, B. S. MOWRY,

Assistant Examiners.

Claims

1. APPARATUS FOR HOLDING A GUN MUZZLE ATTACHMENT AND A GUN BARREL HAVING A MUZZLE END AND A FIRING CHAMBER END WHILE SAID ATTACHMENT IS BEING SECURED TO THE BARREL, SAID APPARATUS INCLUDING A SUPPORT, A FIRST FIXTURE MOUNTED TO SAID SUPPORT AND CONSTRUCTED AND POSITIONED TO ENGAGE AND ACCURATELY LOCATE SAID FIRING CHAMBER END OF THE GUN BARREL, AND A SECOND FIXTURE MOUNTED TO SAID SUPPORT FOR HOLDING AND ACCURATELY POSITIONING SAID MUZZLE ATTACHMENT AT SAID MUZZLE END OF THE BARREL, SAID SECOND FIXTURE BEING CONSTRUCTED TO HOLD SAID ATTACHMENT IN ALMOST EXACT AXIAL ALIGNMENT WITH THE MUZZLE END OF A BARREL HELD BY SAID FIRST FIXTURE BUT AT A PREDETERMINED VERY SLIGHT UPWARD ANGLE RELATIVE THERETO AS THE BARREL AND ATTACHMENT ARE SECURED TOGETHER, TO COMPENSATE FOR THE PRESENCE OF THE MUZZLE ATTACHMENT IN AIMING, THERE BEING MEANS OF INDICATING PRECISELY WHEN SAID SECOD FIXTURE AND ATTACHMENT ARE AT SAID PREDETERMINED VERY SLIGHT ANGLE TO THE MUZZLE END OF THE BARREL.