TacFire Unassembled Rifle Build Kit AR-15 5.56x45mm NATO 16in Barrel 15in Handguard 1-8 Twist 1/2x28 A2 Birdcage Black. With a 1:8 twist rate your new firearm will stabilize everything from 55-grain range ammo to 69 plus grain match projectiles. With the mil-spec fire control group you'll get positive ignition with steel-cased ammo with a traditional 5 to 6-pound trigger pull. And the free-floating handguard will keep your groups tighter than a standard M4 style upper. Once these AR15 Lower Parts are assembled the free-floating barrel has excellent accuracy potential. The TacFire AR-15 Complete Rifle Kit has everything you need for a reliable AR-15 build. Specifications for TacFire Unassembled AR-15 16in Rifle Build Kit: Manufacturer: TacFire Color: Black Fabric/Material: Aluminum Steel Caliber: 5.56x45mm NATO .223 Remington Gun Make: AR Platform Gun Model: M4 AR-15 Gun Type: Rifle Included Accessories: Standard Condition: New Muzzle Device: A2 Flash Hider Handguard Length: 15 in Charging Handle Included: MIL-SPEC Gas Block Journal Size-Diameter: .750 in Barrel Twist Rate: 1-8 Handguard Type: Free-Float Threads per Inch: 1/2x28 Gas System Length: Carbine Length Gun Rail: Picatinny M-LOK Bolt Carrier Group Included: MIL-SPEC Features of TacFire Unassembled AR-15 16in Rifle Build Kit: Build a complete AR-15 that can do it all at an excellent price point with Tacfire; This kit ships to your door unassembled with everything you need less your choice in lower receiver to make a range-ready rifle; With a reliable carbine-length gas system and a free-floated barrel this kit will come together into a gun that's ready to run Package Contents: TacFire Unassembled AR-15 16in Rifle Build Kit 16" Barrel 1:8 Twist/Parkerized 5.56 NATO Bolt Carrier Group 15" Slim M-LOK Free Float Hand Guard Lower Parts Kit w/Trigger & Hammer Mil Spec 6-Position Stock .750 Gas Block Carbine Length Gas Tube Standard Receiver End Plate Mil-Spec/Commercial Castle Nut/Steel Mil-Spec Buffer Tube/Alum 3 oz. Buffer Buffer Tube Spring Mil-Spec Charging Handle Alum Dust Cover Forward Assist A2- 1/2"x28 Thread Bird Cage A2 Muzzle Brake A2 Pistol Grip/Black Upper Receiver 5.56/.223 M4 Feed Ramps The Tacfire Unassembled AR-15 16in Rifle Build Kit is a quality addition to the TacFire lineup. For more great deals on AR15 Lower Parts by TacFire please browse our Tacfire Gun Parts page. Tacfire RK556LPK: Unassembled Rifle Build Kit AR-15 5.56x45mm NATO 16in Barrel 15in Handguard 1-8 Twist 1/2x28 A2 Birdcage Black