Rival Arms Match Grade Drop-In Barrel, V1, For Gen 5 Glock 17, Threaded 1/2x24, 9MM, 1:10 Twist, CNC Machined 416R Stainless Steel Billet RA-RA20G104D It's no secret that the key to great accuracy is good training. After that" it often comes down to a match-grade barrel. Built from high-quality stainless steel" precision polished" and treated with premium coatings" these barrels rival custom work and deliver the best in accuracy and performance" round after round. Threaded barrels and protectors use 1/2-28 threads for compatibility with after-market accessories like suppressors and compensators.