Abstract: A firearm barrel, including rifling formed of an alternating, spirally-extending plurality of grooves and lands defining a twist angle adapted for imparting rotation to a bullet being impelled through the barrel from a chamber end to and exiting a muzzle end. The plurality of lands each include a reduced width component communicating with the chamber end of the barrel for a predetermined distance towards the muzzle end of the barrel. The reduced width component defines an acute angle in relation to a longitudinal axis of the barrel adapted to cause a bullet being fired from the firearm to prevent blow-by gases to exit the barrel in advance of the bullet. A method of forming the firearm and barrel is also disclosed.

Abstract: A firearm barrel, including rifling formed of an alternating, spirally-extending plurality of grooves and lands defining a twist angle adapted for imparting rotation to a bullet being impelled through the barrel from a chamber end to and exiting a muzzle end. The plurality of lands each include a reduced width component communicating with the chamber end of the barrel for a predetermined distance towards the muzzle end of the barrel. The reduced width component defines an acute angle in relation to a longitudinal axis of the barrel adapted to cause a bullet being fired from the firearm to prevent blow-by gases to exit the barrel in advance of the bullet. A method of forming the firearm and barrel is also disclosed.

Abstract: A firearm barrel, including rifling formed of an alternating, spirally-extending plurality of grooves and lands defining a twist angle adapted for imparting rotation to a bullet being impelled through the barrel from a chamber end to and exiting a muzzle end. The plurality of lands each include a reduced width component communicating with the chamber end of the barrel for a predetermined distance towards the muzzle end of the barrel. The reduced width component defines an acute angle in relation to a longitudinal axis of the barrel adapted to cause a bullet being fired from the firearm to prevent blow-by gases to exit the barrel in advance of the bullet. A method of forming the firearm and barrel is also disclosed.

Abstract: A barrel bushing for a semi-automatic pistol. The barrel bushing defines a bore for receiving a barrel therein for reciprocating movement during operation of the pistol. The improvement to the barrel bushing comprises first, second and third annular bearing surfaces formed on inner walls of the bore and against which the barrel moves during operation of the pistol. The first bearing surface contacts and supports the barrel during the recoil phase of operation, and defines a plane parallel to the longitudinal axis of the barrel during recoil. The second and third bearing surfaces reside in axially spaced-apart relation on opposite axially-extending sides of the first bearing surface and define respective planes with respect to the first bearing surface which are parallel to the longitudinal axis of the barrel during lockup and on which opposite upper and lower surfaces of the barrel are supported during lockup. A method of manufacturing the barrel bushing is also disclosed.

Abstract: In a barrel of a semi-automatic pistol, the barrel having fore and aft barrel locking grooves for locking into corresponding fore and aft slide assembly wall segments formed in a slide mounted on a receiver of the pistol when the barrel is in its lock-up position, the improvement comprising adjustment means for precision-fitting the barrel to the dimensions and tolerances of the slide and the receiver of the pistol. The barrel includes a pair of raised contact pads integrally-formed in laterally-spaced relation in the aft locking groove of the barrel to provide an initial vertical interference fit between the aft locking groove of the barrel and the aft locking wall segment of the slide.

Abstract: The invention provides a barrel locking device for automatic pistols, and a sub-caliber conversion therefor. The essential elements of the locking device are the barrel, the aligning cheeks at the rear end of the barrel, the barrel extension member, a link pivotally connected to such barrel extension member and having a hole therein, a slide-stop having a pivot pin for engagement in a transverse through hole in the piston receiver and in the hole in the link, and a barrel locking screw which engages in a threaded hole in the front face of the extension member. Upon tightening of the barrel locking screw the link is rotated forwardly and pulls the barrel and slide into intimate contact with the receiver by engagement of the barrel cheeks with the upper surface of the receiver.