1. An adapter for converting a shotgun to a rifle comprising a barrel having a muzzle end including a cartridge receiving member, a bore sleeve positioned over said cartridge receiving member, a muzzle end piece adjacent said muzzle end, screw threads threadedly securing said muzzle end to the forward end of said barrel, aligned means in said sleeve and cartridge receiving member for securing said sleeve to said cartridge receiving member, extractor means removably secured between said bore sleeve and said cartridge receiving member, retaining means in said bore sleeve and said cartridge receiving member, and locking means on said barrel for securing said barrel within a shotgun, said locking means including a first slip ring collar secured to said barrel, at least one expansible grommet located forward of said slip ring collar, and a second collar disposed between said muzzle and said first collar, said grommet being compressed by rotation of said muzzle end piece on said screw threads.
This invention relates generally to gun bore adapters and more particularly to an improved adapter for converting a standard shotgun of any bore and choke size to a standard rifle for firing high velocity conventional bullet shells therefrom.
The principal object of this invention is to provide an improved rifle bore adapter which can be inserted with minimal skill into a shot gun barrel so as to convert a standard shotgun into a high velocity rifle.
Further, it is an object of the invention to provide a single rifle bore adapter which is utilizable with all standard size shot guns through the use of a plurality of interchangeable sleeves and collars, all of which are designed to be used with a single rifled barrel.
Still further, it is an object of the invention to provide a rifle barrel adapter for shotguns which adapter will provide for conventional extraction and ejection of rifle shells from the rifle barrel by a shotgun which utilizes the existing shot gun extraction and ejection system without modification thereto.
Still another object of this invention is to provide a barrel adapter for shotguns which will cushion the recoil effect of the rifle shot while at the same time providing a secure placement of the rifle barrel within the shotgun barrel and preventing any damage to the shotgun barrel or operating mechanism.
These, together with the other objects, advantages and features of the invention will become more apparent as the specification continues with reference to the accompanying drawings, wherein:
FIG. 1 is an exploded elevational view showing all of the individual components of the rifle convertor for shotguns;
FIG. 2 is an elevational view partly in section showing the muzzle end of the convertor in assembled condition;
FIG. 3 is an elevational view partially in section showing the muzzle end of the convertor within a shotgun barrel and showing the muzzle grommet compressed against the interior bore of the shotgun barrel;
FIG. 4 is an elevational view partially in section showing an alternate embodiment of a muzzle grommet in the assembled condition on the rifle barrel in the non-compressed condition;
FIG. 5 is a perspective view of the alternate embodiment showing the muzzle grommet;
FIG. 6 is an elevational detailed sectional view showing the alternate embodiment of the muzzle grommet in compressed condition within the shotgun barrel;
FIG. 7 is an exploded view of the adapter sleeve, the barrel and the extractor, which is adapted to fit within the cartridge receiving section of the shotgun barrel; and,
FIG. 8 is an enlarged detail view of the adapter sleeve in assembled condition.
Referring now in detail to the accompanying drawings, wherein like reference numerals represent similar parts in each of the views, there is shown the rifle convertor for shotguns generally designated as 10 being comprised of a bore sleeve 12 and a chamber member 14 forming portions of the cartridge receiving member 16. The cartridge receiving member 16 tapers down in external size at 18 forming the outer portion of the barrel 20. An adjustable locking slip ring collar 22 is fitted over the barrel 20 and is secured in place against slippage by set screw 24. The barrel 20 is further provided with an inset male thread 26 which is set apart from the barrel 20 by a vertical shoulder 28. A further reduced cross section 30 of the barrel 20 extends beyond the threaded portion 26 at which point the interior of the rifle barrel 32 is visible.
As can be seen in FIG. 1, there are a plurality of flexible muzzle grommets 34 which are adapted to be slipped over the reduced portion 30 of the rifle barrel 20, the threaded member 26 and which rest on the barrel 20 of the rifle barrel. Further, there is seen a slip ring collar 36 preferably formed out of steel or brass having an interior opening which permits the same to be slipped over the reduced portion 30 of the rifle barrel 20, the threaded member 26 and which will rest upon the barrel 20 of the rifle barrel.
A muzzle section 40 is provided which has the same outer diameter as the slip ring collar 36. The rearward end 42 of the muzzle section 40 is formed having an enlarged interior diameter 44, which is of the same size as the interior of the slip ring collar 36 and also is sized so as to fit over the reduced portion 30 of the barrel 20 and the screw threaded member 26 until enlarged interior diameter 44 completely encircles the barrel 20. The muzzle section is further provided with a threaded portion 46 which is adapted to receive the threaded portion 26 and as the muzzle portion 40 is screwed onto the rifle barrel 20 the slip ring collar 36 and the muzzle grommets 34 are brought into engagement with the locking collar 22, as can be best seen in FIG. 2. It is further clearly illustrated in FIG. 2 that the forward portion 48 of the muzzle section has an enlarged interior cross section 50 which is considerably larger than the barrel 20.
Further, the muzzle section 40 is provided at its forward end 48 with a slot 52, the purpose of which will be discussed as the specification continues.
Referring now specifically to FIG. 7, there is seen the bore sleeve 12 which is provided with a partial annular shoulder or flange 60. This bore sleeve 12 is adapted to fit over the rearward end 62 of the chamber member 14, which rearward end 62 of chamber member 14 is of a reduced outer diameter allowing the bore sleeve 12 to be slipped over the rearward end 62 and brought into abutment with the shoulder 64 of the chamber member 14 which provides a forward limit for the bore sleeve 12. In FIG. 7 it will be noted that the bore sleeve has an outer diameter which is the equivalent size to a 16 gauge shotgun barrel as indicated by the encircled No. 16.
It is to be understood that in the event that the user desires to utilize the adapter with a shotgun of a different bore such as 8, 10, 12, 14, 17, 18 or 20 gauge it will merely be necessary to utilize a bore sleeve of the appropriate diameter while all of the remaining parts and features of the barrel adapter remain unchanged.
Once the appropriate size bore sleeve 12 has been selected by the user, which bore sleeve 12 is compatible with the gun, the bore sleeve 12 is placed over the rearward end 62 of the chamber member 14 and set screws 66 are turned until they fully engage the screw receiving recesses 68 in the chamber member 14 (FIG. 8).
It should be further noted that the bore sleeve 12 is provided with a notch 170 at the lower rearmost portion thereof into which the extractor 72 rests. Further, the bore sleeve is provided with a groove 174 in the interior portion thereof adjacent the lower notch 170 in which the lower portion 76 of the extractor 72 slides. Likewise, the lower portion of the chamber member 14 is provided with a groove 78 in which the upper portion 80 of the extractor 72 slides. A shoulder 82 is provided interior of the notch 170 into which the extractor 72 fits, which shoulder 82 is adapted to engage the downwardly depending forward finger 84 of the extractor 72 thereby preventing accidental dislodgement or displacement of the extractor 72 from the bore sleeve 12 and the chamber member 14 when in the assembled condition.
Once the rifle barrel 10 is in the assembled condition, the entire assembly is inserted into the open breech of the shotgun barrel from the rear by inserting end 48 first. The barrel is fully inserted into the shotgun barrel until such time as the flange 60 engages the breech 88 of the shotgun barrel 90 at which time the shotgun breech is closed.
After the breech is closed, a wedge shaped locking key K similar to a screwdriver blade is inserted into the muzzle end of the barrel until it engages notch 52 at which time the key K is turned clockwise (FIG. 3) causing the collars 36 - 22 to compress the muzzle grommets 34 expanding the outer diameter of the grommets 34 to engage the interior 92 of the shotgun barrel 90 thereby securing the rifle barrel firmly in position within the shotgun barrel. Since the muzzle grommets 34 are flexible, and elastic, they further serve to provide a cushioning device for the forward end 48 of rifle barrel, thus reducing the recoil of the firearm when fired.
Referring now specifically to FIGS. 4, 5 and 6, there is shown an alternate embodiment of the invention, wherein all reference numerals bear the 100 series designation with all parts being identical except for the muzzle grommets. In this embodiment rather than utilizing a plurality of individual muzzle grommets 34 as in FIGS. 1, 2 and 3, a unitary muzzle grommet 134 is utilized. The muzzle grommet 134 is formed from a unitary piece of rubber or the like and has at the ends thereof fully encircling portions 133, 135, respectively. Extending between the encircling portions 133-135 are a plurality of flexible ribs 137, which upon compression caused by the tightening of the muzzle piece 148 on the screw threads 126-146, force the ribs 137 to bow automatically as illustrated in FIG. 6. In this manner the forward portion of the rifle barrel is secured within the shotgun barrel while at the same time providing an air passage which allows the heated gas which builds up between the rifle barrel and the shotgun barrel to escape.