Glossary of Firearms Terms - P

P

• parkerizing: A method of protecting a steel surface from corrosion and increasing its resistance to wear through the application of an electrochemical phosphate conversion coating. Also called phosphating and phosphatizing.

• percussion cap: a small cylinder of copper or brass that was the crucial invention that enabled muzzle-loading firearms to fire reliably in any weather. The cap has one closed end. Inside the closed end is a small amount of a shock-sensitive explosive material such as fulminate of mercury. The percussion cap is placed over a hollow metal "nipple" at the rear end of the gun barrel. Pulling the trigger releases a hammer which strikes the percussion cap and ignites the explosive primer. The flame travels through the hollow nipple to ignite the main powder charge.

• Picatinny rail: a bracket used on some firearms in order to provide a standardized mounting platform.

• pinfire: an obsolete type of brass cartridge in which the priming compound is ignited by striking a small pin which protrudes radially from just above the base of the cartridge.

• plinking: Informal target shooting done at non-traditional targets such as tin cans, glass bottles, and balloons filled with water.

• powerhead or bang stick: a specialized firearm used underwater that is fired when in direct contact with the target.

• pump-action: A rifle or shotgun in which the handgrip can be pumped back and forth in order to eject a spent round of ammunition and to chamber a fresh one. It is much faster than a bolt-action and somewhat faster than a lever-action, as it does not require the trigger hand to be removed from the trigger whilst reloading. When used in rifles, this action is also commonly called a slide action.