On 7 March 2013, the Remington MSR was declared the winner of the precision sniper rifle competition.  Remington announced that the MSR had won on 8 March, and it was publicly confirmed on 9 March.  This was followed by a $79.7 million contract for 5,150 rifles with suppressors, along with 4,696,800 rounds of ammunition to be supplied over the next ten years. The contract was awarded on 12 September 2013.  Remington Defense would produce the Mk 21 sniper rifles and utilized two other companies for other system components, with Barnes Bullets for ammunition and Advanced Armament Corporation for muzzle brakes and suppressors; all three companies are subsidiaries of Remington Outdoor Company. However, it was then decided that the Mk 21 did not conform to SOCOM requirements, and the program was re-competed with the Barrett MRAD selected in 2019 as the Mk 22 Advanced Sniper Rifle solution. The US military opted to use 7.62×51mm NATO, .300 Norma Magnum and instead of the .338 Lapua Magnum the  .338 Norma Magnum chambering in their Mk 22 rifles, which have a field-convertible barrel/chambering switch capability.