firing pin

American  

noun

Ordnance.

1. a plunger in the firing mechanism of a firearm or cannon that strikes the cartridge primer, igniting the propelling charge.

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firing pin British  

noun

1. the part of the firing mechanism of a firearm that ignites the charge by striking the primer

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Etymology

Origin of firing pin

First recorded in 1870–75

Example Sentences

The firing pin holds thousands of pounds of tension in place, and it takes a hard, full-body tug to release it.

From Slate • Jul. 7, 2025

It continued: "If these features were somehow bypassed, a conspicuously off-centre firing pin impression would result."

From BBC • Aug. 16, 2023

Greenberg said his administration has already directed police to remove the firing pin in confiscated guns before turning them over to the state.

From Salon • Apr. 11, 2023

In a quick response, the U.S. team member told the Ukrainian to remove the gun’s breech at the rear of the howitzer, and manually prime the firing pin so the gun could fire.

From Seattle Times • Jan. 27, 2023

Ten seconds more for another gun crew to cogitate on whether disaster hung on the dart of a firing pin.

From "And they thought we wouldn't fight" by Gibbons, Floyd