MEPLAT

A term for the blunt tip of a bullet, specifically the tip’s diameter.

METAL FOULING

Metallic bullet material left in the bore after firing.

METALLIC AMMUNITION

A generic term for rimfire and centerfire ammunition derived from their metallic cases.

METFORD RIFLING SYSTEM

A form of rifling with shallow grooves that are arcs of less than half of the groove diameter.

MACHINE GUN

A fully automatic firearm that loads and fires live cartridges and ejects the spent cartridges continuously when the fire mechanism is held until ammunition is exhausted, the firearm’s designed burst cycle is completed or the firing mechanism is released.

MACHINE REST

Mechanical apparatus used for holding a firearm in a precisely controlled, selected position for testing the accuracy of the ammunition or the firearm.

MAGAZINE

1. A building for the storage of either ammunition or its components. 2. A receptacle for a firearm that holds a plurality of cartridges or shells under spring pressure preparatory for feeding into the chamber. Magazines take many forms, such as box, drum, rotary, tubular, etc. and may be fixed or removable.

MAGAZINE CATCH

The device that retains or releases the magazine in a firearm. Also known as Magazine Latch or Magazine Release.