Magpul UBR GEN2 Collapsible Stock for AR-15/M4 Black

The Magpul UBR Generation 2 Collapsible Stock for AR-15/M4 in black is a purpose-built adjustable buttstock designed to deliver fixed-stock stability with the flexibility of eight position adjustment. Built around a fixed cheek piece, the UBR GEN2 maintains consistent cheek weld across all positions—a critical advantage for shooters transitioning between shooting positions or working with variable optics requiring consistent sight picture. This stock accommodates carbine-length, A5, and SR-25 buffer tube systems, making it compatible with most modern AR platform configurations.

The fixed cheek piece represents a meaningful engineering improvement over earlier collapsible designs that forced shooters to re-establish cheek weld at different collapse positions. Each of the eight positions locks securely, eliminating creep under recoil or from tactical movement. Weighing 1.78 lbs, the UBR GEN2 adds minimal mass while providing the ergonomic benefits of an adjustable platform. The black composite construction resists corrosion and maintains functionality across temperature extremes typical of field use and storage.

This stock serves operators, law enforcement trainers, and serious sport shooters who require reliable length-of-pull adjustment without sacrificing shoulder pocket consistency. The UBR GEN2's multi-position design accommodates shooters of varying builds, body armor configurations, and duty gear setups—essential for teams where firearms rotate between personnel or roles. Patrol officers, tactical team members, and competitive shooters benefit from the ability to fine-tune length while maintaining a solid cheek weld for accurate shot placement.

The UBR GEN2 represents the evolution of Magpul's original Utility/Battle Rifle concept, refining the platform based on extensive operator feedback. In the collapsible stock category, it bridges the gap between fixed stocks and lightweight commercial adjustables, offering the rigidity and ergonomics serious users demand without unnecessary weight or complexity.