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half cock
The position of the hammer when it is being retracted and held by the sear so It cannot be released by a normal pull of the trigger.
hammer
The part of the action that drives the firing pin forward.
hammer block
A safety device that separates the hammer from the firing pin except when the trigger is pulled.
hammer spur
The extension on an exposed hammer that acts as a cocking aid.
hammerless
A firearm whose hammer and striker (firing pin) are concealed within the metal frame.
handgun
A gun designed to be fired from one hand, capable of being concealed on the person and with a barrel less than 16 inches long. Until the mid-1980s the most common type was a revolver, with a rotating cylinder usually holding 6 cartridges. Since then, production of revolvers has declined and the dominant handgun has become the semi-automatic pistol, which uses a removable ammunition magazine (also called a "clip"), usually located in the handle of the gun. Each firing of the pistol forces a new cartridge up the magazine and into the chamber. A typical 9mm-caliber pistol has a magazine capacity of 8-10 cartridges.
head
The portion of the cartridge case that contains the primer, also called the base.
head space
The distance from the face of the closed breech of a firearm to the surface in the chamber on which the cartridge case seats.
high brass/high cup
Shotshells having a high metal head construction.
hinged frame action
A design where a level located on the top, side or under the frame is used to open the action. The barrel or barrels then pivot either up, down or to the side for loading or unloading. When the action is closed, the barrel(s) breech swings against the standing breech.
hollow point bullet
A bullet with a cavity in the nose to enable expansion.
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John McCain
appeared on 2,500 movie screens in Spring 2001 to urge parents and children to save lives by keeping guns locked up and out of schools. play video read more

 Safe Carry
What are the best ways to carry a firearm comfortably and safely? Our Gun Safety Program explains which carrying techniques are safe in specific situations.

 Safety Gear
You should always wear equipment to protect your eyes and ears when firearms are discharged, whether you are shooting or simply observing.

 Cleaning Firearms
See our Gun Safety Program for expert tips on how to safely clean and maintain firearms.