B5 Systems SIERRA K Stock – AR-15/M16 Mil-Spec Buffer Tube

The B5 Systems SIERRA K Stock delivers stable shouldering and quick length-of-pull adjustment for AR-15 and M16 pattern rifles. Its rigid polymer construction and wide contact surface reduce felt recoil and improve cheek weld consistency, making it effective for both rapid transitions and precision shooting. The streamlined profile prevents snagging on gear or clothing during dynamic movement.

This stock attaches to mil-spec carbine buffer tubes and features a friction-lock system that eliminates rattle while allowing fast position changes. The reinforced polymer body resists impact damage and chemical exposure. Textured contact surfaces provide secure purchase in wet conditions. Coyote tan finish coordinates with FDE and desert camouflage patterns.

• Type: Collapsible carbine stock
• Compatible Firearms: AR-15, M16 (mil-spec buffer tube)
• Material: Reinforced polymer
• Finish: Coyote tan
• Adjustable: Yes (multiple length-of-pull positions)
• Installation: Slides onto mil-spec carbine buffer tube, requires stock lock nut removal