Patent ID: 7380487

Claim:
A recoil mechanism for a gun having a frame with a barrel and a slide that is movable rearwardly of the frame and barrel, when the gun is fired, the mechanism comprising: a cylinder having a rear end with an external flange and an internal diaphragm spaced forwardly of the flange and disposed between a rear chamber and a front chamber both defined in the cylinder; a round nut fixed to the frame; an axle extending in the cylinder, the axle having a rear end threaded to the round nut and a collar space forwardly of the rear end and being forward of the diaphragm and trapped in the front chamber by the diaphragm; a first spring around the cylinder, the first spring having a front end abutting the slide and a rear end abutting the flange; a second spring extending at least partly in the rear chamber and having a rear end abutting the round nut and a front end abutting the diaphragm; a third spring in the front chamber, the third spring being shorter in length than the front chamber; the front chamber having a front entry end and a set screw closing the front entry end of the front chamber; a magnet magnetically attractively engaged to a front end of the slide and to a front end of the cylinder before the gun is fired; and a support for holding the magnet to the frame comprising one of: an extension of the axle in the front chamber, extending through the set screw and the magnet, and a locking nut threaded to a front end of the extension for fixing the magnet to the axle and frame; and a base fixed to the frame and to the magnet for fixing the magnet to the frame; the magnet attracting the slide and the cylinder in a forward direction that is opposite to a rearward recoil direction of motion of the slide when the gun is fired; and upon firing of the gun, a force of gases in the barrel acting on the slide to move the slide in the rearward recoil direction, rises to a point which overcomes an attractive force between the magnet and the slide so that the slide starts to move in the rearward recoil direction, and, after a time lag, the slide engages the cylinder causing the cylinder to also move in the rearward recoil direction; the time lag being selected to allow a maximum expansion of gases from the barrel for propelling a bullet from the barrel while the slide recoils, so that the bullet has improved range; the third spring functioning in the front chamber to become compressed later during the recoil of the slide to absorb a remainder of recoil energy of the slide, for decelerating any further recoil of the slide, with most recoil energy of the slide being absorbed by a progressive compression of the first spring and the second spring.