US Army The Army just picked a new, multi-caliber sniper rifle: the MK22 Multi-role Adaptive Design, or MRAD. Now it wants a new class of ammunition to make snipers deadlier and more destructive against enemy personnel and equipment. The Army just picked a new, multi-caliber sniper rifle. Now, it wants a new class of ammunition to make snipers deadlier and more destructive against enemy personnel and equipment. Under its Precision Sniper Rifle, or PSR, effort, the service awarded a $50 million contract in late March to Barrett Firearms Manufacturing Inc. for the MK22 Multi-role Adaptive Design, or MRAD, sniper rifle, which can be chambered for .338 Norma Magnum, .300 Norma Magnum and 7.62x51 NATO ammunition.