5mm round

The  is an ammunition type found in Fallout, Fallout 2, Fallout 3, Fallout: New Vegas and Van Buren. It is used by various weapons, such as the Minigun.

Van Buren
5mm rounds are still in use by NCR in 2253, and were used in all of NCR's standard-issue assault rifles. All of the NCR goons in Hoover Dam and Ballistic Orbital Missile Base 001 carry a bunch of spare magazines.

Used in

 * Assault Rifle