The TacFire 10.5″ Unassembled AR 300 Blackout Pistol Build Kit (brand part no. PK300LPK-10) gives builders nearly every part needed for a 300 Blackout pistol project with a longer 10.5″ barrel. The kit centers on a black parkerized 10.5″ barrel with a 1:7 twist rate and a 5/8×24 spiral-fluted Krink-style muzzle device, paired with a slim M-LOK free-float handguard and a 7075-T6 billet aluminum stripped upper. A 5.56 bolt carrier group, mil-spec charging handle, dust cover, forward assist, heavy pistol buffer, pistol-length gas tube, low-profile gas block, complete pistol buffer tube, A2 black pistol grip, and lower parts kit round out the build — all manufactured in the USA. A stripped lower receiver is required separately to complete the build.

Key Specifications

• Includes a black parkerized 10.5″ barrel with a 1:7 twist rate.
• Barrel is fitted with a 5/8×24 spiral-fluted Krink-style muzzle device.
• Features a slim M-LOK free-float handguard.
• Built around a 7075-T6 billet aluminum stripped upper.
• Includes a 5.56 bolt carrier group and mil-spec charging handle.
• Comes with a complete pistol buffer tube assembly and A2 black pistol grip.
• Ships with a full lower parts kit for finishing the build.
• Constructed of steel and aluminum with a black parkerized finish.
• All components are manufactured in the USA.

Frequently Asked Questions

Does this kit include a stripped lower receiver? No, a stripped lower receiver is required separately to complete the build.

What twist rate is the barrel? A 1:7 twist rate, suited to a range of 300 Blackout bullet weights.

What handguard does it use? A slim M-LOK free-float handguard.

Buy the TacFire 10.5in 300 Blackout Pistol Build Kit

Start your next 300 Blackout pistol build with a longer 10.5″ barrel and nearly every part included. Order the TacFire Pistol Build Kit from our Lubbock, Texas gun shop for fast, insured shipping — or browse more AR lower parts kits.