Franklin Armory F17-X Complete Upper Features The Franklin Armory F17-X Complete Upper Receiver uses the new Osprey Defense slim piston system which automatically adjusts the gas system for suppressed or unsuppressed shooting without requiring the user to make any manual changes. This self-regulating piston design combined with the .17 WSM chambering delivers a cleaner-shooting flatter-trajectory setup ideal for varmint and pest control work at extended ranges. The 16 inch barrel carries a 1:9 twist rate matched to stabilize .17 WSM projectiles and is threaded in the common 1/2x28 pitch giving shooters broad compatibility with aftermarket suppressors. A low-profile gas block and the Aura muzzle device round out a system built specifically around suppressor-ready use. A proprietary 15 inch M-LOK handguard features an integrated barrier stop and indexing point giving shooters a stable platform to brace against cover or barriers during field use while remaining fully M-LOK compatible for lights bipods or other accessories. The upper arrives optics ready letting shooters mount their preferred red dot or scope without additional machining. A standard charging handle and the F17 proprietary bolt carrier complete a purpose-built piston system engineered specifically around the .17 WSM cartridge. Shipping with a 20-round magazine this Franklin Armory F17-X Complete Upper is a turnkey solution for AR owners wanting a dedicated piston-driven pest control upper available for sale at GrabAGun. Franklin Armory F17-X Complete Upper Specifications Manufacturer: Franklin Armory Model: F17-X Complete Upper Caliber: .17 WSM Barrel Length: 16 Thread Pitch: 1/2x28 Twist Rate: 1:9 Handguard: 15 M-LOK Gas System: OPS Piston Gas Block: Low Profile Muzzle Device: Aura Sights: Optic Ready Color: Black Material: Steel Aluminum Capacity: 20 Rounds Available At: GrabAGun