The Proof Research PR15 barrel (part 143377) is a 14.5-inch .223 Wylde barrel with a 1:7 twist that stabilizes heavy 5.56 bullets. It has a 1:7 twist and a 5/8-24 threaded muzzle for brakes, flash hiders or suppressor mounts. A .223 Wylde chamber safely fires both .223 Remington and 5.56 NATO.
- Brand: Proof Research
- Line: PR15 (AR-15)
- Chambering: .223 Wylde
- Barrel length: 14.5"
- Twist rate: 1:7
- Muzzle thread: 5/8-24
- Listed weight: 2.95 lb
- Part number: 143377
