Floor Plate
Also: Floorplate · Bottom Metal
The bottom of a fixed internal magazine on a bolt rifle. A hinged floor plate drops open to dump unfired rounds without cycling them through the chamber.
On a bolt rifle with an internal box magazine, the floor plate is the metal panel that closes the underside of the magazine well. A hinged floor plate is the practical version: a latch releases it so the spring and stacked cartridges drop into your hand, letting you unload without running every live round across the chamber.
Floor plates are part of the bottom metal that ties the action into the stock. Many precision builds instead use a detachable box magazine for faster reloads, but a solid hinged floor plate remains a clean, rugged hunting setup.