The Mark 4 is offered in 3 different versions. All are chambered in 6.5 Grendel with 20, 16, and 10.5-inch barrel options.
MARK 4: SASS
SASS (Semi-Automatic Sniper System)- Chambered in 6.5 Grendel with a 20-inch Bear Creek Arsenal parkerized heavy barrel with a 1:8 twist and a rifle-length gas system. Over half of the barrel length is bull barrel with a diameter of .980 inches to maintain accuracy at longer ranges with multiple shots. We suggest using Hornady Black 123 grain ELD for maximum potential. This is our most accurate platform. Break into the world of AR-10 range and accuracy while staying in an AR-15 platform.
MARK 4: PATROL
Chambered in 6.5 Grendel with a 10.5-inch Bear Creek Arsenal parkerized heavy barrel, with a 1:8 twist and a pistol-length gas system. We suggest using Hornady Black 123 grain ELD for hunting or self-defense situations. This is our flagship upper that we suggest for multiple uses such as hunting, home defense, or mission and destination unknown situations. This basically can replace the ballistics of a 5.56 but with a shorter PDW-like package.