With machining being handled in-house, CMC Barrels said the proprietary processes and quality control inspection allow for an "ultra-precise barrel with enhanced slide fit and lockup for improved accuracy." Barrel specs include: 416R Stainless Steel Six-groove cut rifling 1:10 Right-hand twist Double-honed to produce the smoothest bore possible Stress relieved SAAMI, match-grade precision chambering Final hardness of 38-42 Rockwell C Straight fluting for aesthetic purposes Threaded options available for suppressor use For maximum consistency, accuracy, and quality, CMC Match Precision Glock Barrels feature "finished bore dimensions held to +/-0.0005 inch tolerance from nominal groove and bore dimensions but the dimensions are uniform within 0.0002." The bead-blasted, satin finish barrels are available in: Stainless: uniform satin blast finish with ultra-low friction hBN (Hexagonal Boron Nitride) bore and chamber Bronze TiCN: with ultra-low friction hBN (Hexagonal Boron Nitride) bore and chamber Black DLC: with ultra-low friction hBN (Hexagonal Boron Nitride) bore and chamber