Franklin Armory F17-L Complete Upper Features The Franklin Armory F17-L upper kit is built around a proprietary F17 gas system engineered specifically to reliably cycle the high pressure .17 WSM cartridge in an AR pattern platform. An OPS piston works alongside a low profile gas block to keep the system running smoothly while reducing fouling in the upper receiver compared to a direct impingement design. The 20 inch barrel carries a 1:9 twist rate matched to the .17 WSM round for consistent accurate performance at extended range. A standard bolt carrier and charging handle keep the manual of arms familiar to anyone already comfortable running an AR platform rifle. A 15 inch handguard integrates a barrier stop giving shooters a stable point of contact when working around cover vehicles or shooting positions. The barrel is threaded 1/2x28 and finished with Franklin Armory s Aura muzzle device both doing double duty for recoil management and compatibility with muzzle accessories. The upper ships optics ready so shooters can mount their red dot or magnified optic of choice right out of the box. Finished in black and designed as a 10 round capable platform the Franklin Armory F17-L upper kit is available for sale at GrabAGun for anyone looking to add a long range rimfire option to their AR collection. Franklin Armory F17-L Complete Upper Specifications Manufacturer: Franklin Armory Caliber: .17 WSM Barrel Length: 20 Handguard: 15 Integrated Barrier Stop Twist Rate: 1:9 Thread Pattern: 1/2x28 Gas System: F17 Proprietary with OPS Piston Muzzle Device: Aura Low Profile Gas Block Charging Handle: Standard Bolt Carrier: Standard Sights: Optic Ready Color: Black Available At: GrabAGun