The Spike’s Tactical M4 Complete Stock Kit (brand part no. SAK0701-K) bundles every part needed to finish the back end of an AR-15 lower receiver in one package, built around Spike’s ST-T2 heavy carbine buffer. The kit includes a 6-position mil-spec buffer tube, an M4 collapsible buttstock, a receiver end plate, a castle nut, a buffer spring, and the ST-T2 buffer itself, so builders are not sourcing each of those parts individually from different vendors. The ST-T2’s added weight over a standard carbine buffer helps smooth out an AR-15’s recoil impulse and cycling, particularly on shorter-barreled or gas-system-tuned builds. Because everything ships as a matched kit, fit and function are dialed in without guessing at compatible parts.

Key Specifications

• Includes a mil-spec, 6-position buffer tube.
• Includes an M4 collapsible buttstock.
• Includes a receiver end plate, castle nut, and buffer spring.
• Built around the ST-T2 heavy carbine buffer for smoother cycling.
• Sold as a complete kit, not individual components.

Frequently Asked Questions

What parts are included in this kit? A 6-position buffer tube, M4 collapsible buttstock, receiver end plate, castle nut, buffer spring, and the ST-T2 heavy buffer.

What does the ST-T2 buffer do? Its added weight over a standard buffer helps smooth out recoil impulse and cycling.

Buy the Spike’s Tactical M4 Complete Stock Kit

Finish your lower in one order with a matched, ready-to-install kit. Order this Spikes Tactical kit from our rifle stock selection, and our Lubbock, Texas team will get it shipped fast.