DPMS Barrel Break-In Procedures

DPMS manufactures a line of civilian semi-automatic rifles based on the military AR-15/M-16 design. The rifles are available in calibers ranging from .204 Ruger to 7.62 mm. The DPMS .223 Remington Panther Bull features a 20-inch barrel made of 416 stainless steel and an upper receiver of aircraft aluminum alloy. A black Zytel thermoplastic stock is standard and the Panther Bull is supplied with two 30-round magazines.

  1. Break-In Schedule

    • DPMS recommends a 100-round barrel break-in period for all rifles. The barrel and chamber should be cleaned and lubricated after every round for the first 25 rounds, then after every 10 rounds up to 100 rounds. Maximum accuracy will be obtained after 200 rounds have been fired. Barrel and chamber cleaning require separating the upper receiver from the lower receiver.

    Receiver Separation

    • Unload the weapon and point it in a safe direction. Push the takedown pin on the lower left of the receiver out the right side of the receiver until it stops. Pivot the lower receiver down from the upper receiver. Push the front pivot pin from the left side of the receiver out the right side of the receiver until it stops. Separate the upper receiver from the lower receiver.

    Cleaning

    • Attach a barrel brush to a barrel cleaning rod. Wet the brush with rifle bore cleaner. Insert the barrel brush into the barrel from the receiver end and push the brush all the way out the muzzle. Do not reverse direction or pull the barrel brush back through the bore. Remove the barrel brush from the barrel cleaning rod at the muzzle end of the rifle, then back the cleaning rod out of the bore. Clean the chamber with cleaning patches wet with rifle bore cleaner. Use a worn barrel brush and rifle bore cleaner to remove deposits from the locking lugs and gas tube.

    Lubrication

    • Attach a gun cleaning rod moistened with gun oil to the end of the gun cleaning rod. Insert the oiled patch into the barrel from the receiver end and push the patch all the way out the muzzle. Do not reverse direction or pull the oiled patch back through the bore. Remove the patch from the barrel cleaning rod at the muzzle end of the rifle, then back the cleaning rod out of the bore. Lubricate the chamber lightly with a cleaning patch moistened with gun oil. Reassemble the lower receiver to the upper receiver.