Rosco Bloodline match-grade 9mm barrel for Glock 17 Gen 1-4. Drop-in upgrade that improves accuracy and cycling reliability over the stock OEM barrel, built from 416R stainless steel and finished in Melonite black nitride for corrosion resistance. Designed to run with SAAMI-approved factory ammunition; no fitting or headspace work required on an OEM Glock 17 slide and frame. Specs Brand: Rosco Manufacturing Manufacturer Part Number: ROSBL-G17-9MM-M-STD Caliber: 9mm Luger Length: 4.49" overall (Glock 17 OEM length) Twist: 1:10 Material: 416R stainless steel, broached / honed / polished, Melonite black nitride finish Drop-in fit - no gunsmithing required on stock Glock 17 slides and frames Fitment Glock 17 Gen 1, Gen 2, Gen 3, Gen 4 Not compatible with Gen 5 (different lockup geometry) Compatible with aftermarket Glock 17-pattern slides built to Gen 1-4 spec (Lone Wolf Timberwolf, SCT 17, PSA Dagger Full Size, etc.) Aftermarket barrels benefit from a short break-in period of 100-200 rounds to seat the chamber and extractor against the new barrel surface. See our slide break-in guide for the full procedure. GLOCK is a federally registered trademark of Glock, Inc. and is one of many trademarks owned by Glock, Inc. or Glock Ges.m.b.H. Neither 3CR Tactical nor this site are affiliated in any manner with, or otherwise endorsed by, Glock, Inc. or Glock Ges.m.b.H. The use of "Glock" on this page is merely to advertise the sale of aftermarket Glock-compatible pistol components. For genuine Glock, Inc. and Glock Ges.m.b.H products, visit https://us.glock.com .