Stag Arms Stag-15 M4

Stag Arms occupies a distinct position in the AR-15 market: they are one of the only manufacturers producing factory left-hand AR-15 uppers at scale, making the Stag-15 M4 the natural first choice for left-handed shooters who want a purpose-built rifle rather than an afterthought adaptation. Both right-hand and left-hand configurations share the same 16-inch chrome-lined barrel, mil-spec forged receivers, and carbine-length gas system, so southpaws get the same quality without paying a premium for the privilege.

The barrel is 4140 chrome moly steel with a chrome-lined bore and chamber, the most durable combination for sustained fire and adverse conditions. Stag uses mil-spec bolt carrier groups with properly staked carrier keys and MPI-tested bolts machined from Carpenter 158 steel. The lower receiver accepts any mil-spec lower parts kit, and the M-LOK handguard provides a lightweight, snag-free profile with mounting real estate for lights, grips, and slings. The trigger is a standard mil-spec two-stage with a consistent 7.5-pound pull that clears cleanly.

At $899, the Stag-15 M4 sits in a competitive tier against the Aero M4E1 and BCM Recce builds, but its left-hand availability is unmatched. Quality control is consistent, and Stag backs every rifle with a limited lifetime warranty. This is a straightforward, well-executed mil-spec AR-15 that rewards upgraders: the lower accepts any aftermarket trigger, the handguard swaps without tools, and the upper pairs with any mil-spec lower.