Abstract: An ambidextrous bolt catch device, apparatus, system and methods for using are provided. Four main components include a bolt catch finger, lever system and plunger rod assembly with torsion spring. The lever system includes a right release lever and a left release lever; the left lever is an integral part of the bolt catch finger. The plunger rod assembly abuts and connects the right and left levers; a torsion spring on the rod creates tension causing rotation of the bolt catch finger in a downward or upward position. In an upward position, the bolt catch finger engages the bolt, retains the bolt in a rearward position, and signals the operator that the magazine is empty. The bolt engaged by the finger is held rearward in a safe, reliable manner to allow an unobstructed view of the firearm chamber until manually released using either the right or left release lever.

Abstract: Automatic and semi-automatic firearms of remarkably reduced mass yet capable of long-range accuracy because of unique recoil reduction are characterized by (A) a temporary combination of a barrel, an integral breech and a separable chamber that in operation of the firearm is moved by a compressed spring distally before and while a chambered cartridge is fired, (B) run-out of such temporary operative combination diminishes firearm recoil, (C) recoil of the temporary operative combination recompresses the spring and (D) the separable chamber is loaded with a round while spatially separated from the breech and barrel.

Abstract: Gas-operated automatic and semi-automatic guns are improved by providing their barrels with unique exterior surface configurations to reduce the weight of their barrels while retaining the barrels' original stiffness and to cause the barrels to dissipate heat faster.

Abstract: New multifunctional muzzle attachments for firearms providing substantial improvement in shooting accuracy in comparison with prior known muzzle attachments are disclosed that simultaneously provide a combination of four different functions, namely, (1) compensate for gun rise (aka muzzle climb), (2) serve to reduce recoil (aka muzzle braking), (3) reduce flash around the muzzle when the firearm is fired (flash hiding) and (4) an interface for a suppressor. This is made possible by the unique combination of (a) a slotted baffle fixed in the distal end of the new cylindrical attachments and (b) a plurality of longitudinal narrow slots between the distal and proximal ends spaced apart around and through the peripheral cylindrical wall.

Abstract: A projectile for firing from a self-loading firearm is provided that will rmit the self-loading mechanism to function while delivering a targeting projectile of reduced range and striking capacity. These latter characteristics may be varied in accordance with a designer's preference.

Abstract: The safety of semi-automatic pistols and like firearms is improved by making them double action only combined with novel features that include use of roller bearings for support of trigger and sear assemblies, structuring them for constant pressure trigger pull, automatic blocking the firing pin from reaching the cartridge until the firearm is fully locked in the battery position and structuring operation of the sear so it can engage the firing pin only when the trigger pulls it rearward.

Abstract: The safety of semi-automatic pistols and like firearms is improved by making them double action only combined with novel features that include use of roller bearings for support of trigger and sear assemblies, structuring them for constant pressure trigger pull, automatic blocking the firing pin from reaching the cartridge until the firearm is fully locked in the battery position and structuring operation of the sear so it can engage the firing pin only when the trigger pulls it rearward.

Abstract: The safety of semi-automatic pistols and like firearms is improved by making them double action only combined with novel features that include use of roller bearings for support of trigger and sear assemblies, structuring them for constant pressure trigger pull, automatic blocking the firing pin from reaching the cartridge until the firearm is fully locked in the battery position and structuring operation of the sear so it can engage the firing pin only when the trigger pulls it rearward.