The TacFire SSRK556LPK Lower Parts Kit Unassembled Rifle Kit brings together a complete AR-15 upper and lower parts set for builders who want a cohesive, reliable 5.56 NATO/223 Rem platform. Featuring a 16" M4 contour barrel with a nitride finish, a 15" MLOK free float handguard, and a birdcage flash hider with 1/2"-28 threads, this kit is designed to deliver consistent performance and smooth operation once assembled. The stripped billet upper receiver with M4 feed ramps, Mil-Spec charging handle, and USA-made lower parts kit provide a solid foundation for a dependable semi-auto build.

This unassembled kit is ideal for shooters who enjoy customizing their AR-15 from the ground up, whether for range use, training, or general-purpose shooting. The included 6-position collapsible stock, A2-style pistol grip, buffer tube assembly, and complete small parts selection allow you to finish a compatible Mil-Spec lower with confidence and precision. TacFire’s attention to detail and proven component quality make this kit a practical choice for builders seeking a straightforward, well-matched parts set.

Key Features:

• Manufacturer: TacFire
• Model: Lower Parts Kit
• Caliber: 223 Rem/5.56 NATO
• Action: Semi-Auto
• Barrel Length: 16"
• Threaded Barrel: 1/2"-28 tpi
• Firearm Fit: AR-15 Platform
• Stock Description: 6 Position Collapsible
• Grip Type: A2 Style Pistol Grip
• Includes: Upper Assembly Parts And Lower Parts Kit
• Twist: 1:8"