• Proprietary Feed Ramp, contoured specifically for .45ACP ammunition, ensures feed reliability and increased ammunition compatibility. 

• .578-28 Threading

• 4150 CMV Steel

• 1-in-16″ Twist Rate

• QPQ Nitride Treated

• .75″ (Medium) Profile

• Quarter Circle parts are designed to work within mil-spec perimeters.  However, for optimum performance we recommend using QC10 parts for all your core elements, (Receivers, bolt, barrel and adjustable buffer system). 

• Made For - Not Modified.  Every QC10 product is engineered specifically for pistol caliber ammunition, not modified from an existing platform, increasing functionality, reliability and overall performance. 

Note:

*Barrels are measured from the end of the muzzle to the end of the breech/feed ramp. Approximately1”  of the barrel rests inside the upper receiver upon installation, resulting in an installed length of 1″ less than listed overall length.