223 Wylde is a hybrid of the 223 REM and 5.56. 223 Wylde has a chamber throat that is tighter than the 5.56 achieving better accuracy but still reliably functional with 5.56 ammunition. All DI barrels include stainless steel tunable gas block.Features :Profile: DMR,Length: 18";"Gas placement: Rifle,Rifling: Button 8 twistWeight: 2.534 lbsMade from 416R Stainless SteelHand-LappedM4 Feed ramps1/2-28 Threading"1" MOA guaranteed,