A lightweight but solidly built AR-15-style buttstock, the American Built Arms Urban Assault Stock (UAS) stows in its most compact form, yet features a spring-loaded buttpad that can be set to deploy to any of four lengths (for a total adjustment of 1.25") at the push of a button.
Magpul’s ubiquitous Precision Rifle/Sniper (PRS) buttstock is now in its third generation, and the newest iteration, although optimized for use with rifle-length buffer tubes, can also be configured to accommodate mil-spec carbine- and A5-length extensions.
A modern stock upgrade for M14/M1A-style rifles, the Blackfeather RS modular chassis is precision-machined from 6061 aluminum alloy with a hard coat anodized finish and patterned from the U.S. G.I. fiberglass stock.
The AR-15 was originally conceived to be a comparatively lightweight firearm, and many modern enthusiasts of the platform choose to take that notion to the extreme by selecting ultra-light components for their rifle builds.
Fabrique Nationale’s SCAR line of semi-automatic carbines are fine guns in their own right, but the Belgian company’s decision to use a proprietary buttstock design limits the amount of customization that can be made to the firearms.