Recoil buffer

A recoil buffer is a factory-installed or aftermarket component of firearms which serves to reduce the velocity of and/or cushion the impact of recoilling parts of a firearm. The simplest form is just a resilient/deformable material (leather, rubber, polymer,... e.g. a rubber butt pad on a shotgun) or a spring is inserted into the recoil train -- the path/part(s) from recoil impulse (equal and opposite to bullet/payload impulse) to the mounting point(s) where the firearm contacts a mechanical holder such as a tripod or human upper torso. Reducing the initial jolt, the rate and/or extent of rearward displacement, and/or any internal impacts in the operating parts of a firearm can reduce the shooter's perception of recoil, and may also work to extend the life of the mechanism and its parts. Much more sophisticated designs use hydraulic or pneumatic shock absorbers; systems of springs, cams, levers, et c. to modify, dampen, or dissipate the rearward impulse generated as the projectile is fired down the bore of the firearm. Aftermarket buffers are often moulded bumpers or additional springs placed between operating metal parts which impact one another, such as the slide and the frame of a semi-automatic pistol. This type of buffer cushions the battering force of repeated metal-metal impact, reducing wear on parts and lengthening the service life of the firearm. Reduction of perceived recoil discomfort is an immediate added benefit of this type recoil buffer. Some pneumatic recoil buffers used in firearms are fast, low-power gas springs. When compressed, they present initial resistance as the rod-to-seal grip is broken and then they move in a regular manner. An additional small spring can be used inside the gas spring if rapid turnaround times are needed. Springs twist and the coils try to ride over each other when moving and all this chaotic movement does not exist with gas springs, hence reducing twist and jump of the firearm. These features are very advantageous. Fine tuning of the spring power is also possible by altering the internal gas volume. This design for firearms was invented and patented by Collins and Shipman of Bedford UK and Bergstrom in the US in 2001.