Alliant Techsystems’ (ATK) spinoff company Vista Outdoor has won a contract worth $52 million for Mk. 311 Mod 3 frangible ammunition to supply the US Army, with a completion date of June 22, 2022, according to the June Department of Defense contracts press release. The contract is likely for 100 million rounds of ammunition or more, which will probably be used mostly for training at ranges with limited backstops.
Sectioned 5.56mm rounds. In the center is Mk. 311 Mod 0 Frangible, which uses a 50gr bullet with gilding metal jacket and a frangible copper matrix. To its right is Mk. 255 RRLP, which uses a 62gr bullet of similar design. On the far right is the 70gr TSX “Brown Tip”. Image credit: Wolfganggross, used with permission.
The Mk. 311 round – better known by its ordnance code “AA40” – is loaded with a 50gr frangible bullet, identifiable by a purple tip. The projectile is make of a lead free powder matrix, wrapped in a gilding metal jacket. It is similar to the Mk. 255 Reduced Ricochet Limited Penetration (RRLP) round, which has a heavier 62gr bullet. In addition to being used in training at ranges where more robust projectiles might damage the backstops, both Mk. 311 and Mk. 255 see use in special operations both because they reduce the chance of ricochet in close quarters (such as on a ship) and because they offer increased lethality at short ranges.