Description

AR-15 Trigger & Selector Bundle – ALG Defense QMS Trigger + Atrius 3-Position Super Selector
This bundle pairs a proven, duty-oriented trigger with a robust 3-position selector for builders who want reliability first—without the grit of a basic mil-spec setup. The ALG Defense QMS (Quality Mil-Spec) Trigger delivers a smoother pull than typical stock triggers by honing the sear surfaces while maintaining standard geometry and full-power ignition. It’s built to meet traditional mil-spec standards, with a ~6.5 lb single-stage pull and a full-force hammer spring for dependable primer strikes across ammo types.

Matched with it is the Atrius Development 3-Position Super Selector, providing SAFE / SEMI / SUPER-SEMI modes with positive detents and a crisp 90° throw for confident engagement and fast transitions. Together, this kit is ideal for hard-use rifles, training guns, and compliance-minded builds where familiar trigger characteristics and enhanced selector capability matter.

Features:

ALG Defense QMS Trigger:

Single-stage trigger with mil-spec geometry and enhanced smoothness
~6.5 lb pull (above 5.5 lb minimum spec; below typical upper limit)
Sear surfaces honed to reduce gritty feel without altering geometry
Full-force hammer spring for reliable ignition
Trigger/hammer made from 8620 alloy steel; disconnector from 1070 high carbon steel
Includes improved 4140 chrome-moly trigger/hammer pins (oversized +0.001″ for reduced play)

Atrius 3-Position Super Selector:

Three positions: SAFE / SEMI / SUPER-SEMI
Positive detents and tactile clicks with 90° throw
Heat-treated steel construction with corrosion-resistant finish
Drop-in fit for most mil-spec lowers (minor fitment may be required)

Specifications:

Trigger (ALG QMS):

Type: Single-stage mil-spec pattern
Pull Weight: ~6.5 lb (varies slightly by rifle)
Materials: 8620 alloy steel (trigger/hammer), 1070 steel (disconnector)
Springs: corrosion-resistant, military spec; full-force hammer spring
Pins: 4140 chrome-moly, +0.001″ diameter (slip fit)

Selector (Atrius):

Positions: SAFE / SEMI / SUPER-SEMI
Throw Angle: 90°
Material: Heat-treated 4140 steel
Finish: Corrosion-resistant finish
Compatibility: Mil-spec AR-15 lowers / FCGs (.223/5.56/.300 BLK)

SKU: BUNDLE-QMSASS

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