Feed ramp

A feed ramp is a basic feature of many breech loading cartridge firearm designs.

It is a tightly machined and polished piece of metal which guides a cartridge from the top of the magazine into the firing chamber of the barrel.

When the weapon is fired and the spent case is ejected, the feed ramp functions to direct a fresh cartridge from the magazine into firing position; that is, the fresh cartridge slides along the feed ramp into battery.

The need for the cartridge to slide both forwards and upwards along the feed ramp and into the barrel is the primary design consideration that makes the ogive the preferred shape for all modern automatic pistol rounds (a hollow point bullet is a truncated ogive), as there are many other shapes that are stable in ballistic flight.

A rough surface or the presence of debris on the feed ramp can knock cartridges off-center, inducing a jam.

Rear side of a CZ-75B pistol barrel showing the (here dirty) feed ramp.
Locking lug feed ramp on AR-15 barrel nut.