Expo Arms Mil-Spec Builder AR-15 Lower Parts Kit & MIMTAC CORE Trigger

Expo Arms Mil-Spec Builder AR-15 Lower Parts Kit - XP-LPK-BLDR
The Expo Arms AR-15 Builder Lower Parts Kit gives a stripped lower a Mil-Spec foundation, including the safety selector and every other small part except the pistol grip and fire control group.

Kit Includes:

• Safety selector with detent and spring
• Bolt catch with roll pin, detent, and spring
• Magazine catch with button and spring
• Takedown and pivot pin assemblies with detents and springs
• Buffer retainer with spring

Every component is manufactured to Mil-Spec dimensions for drop-in compatibility with standard AR-15 lower receivers from any manufacturer, leaving the pistol grip and fire control group as the builder's choice. This kit also works well as a spare-parts supply for field or range repairs.

Expo Arms manufactures Mil-Spec AR-15 components in the United States, backed by a Limited Lifetime Warranty against manufacturer defects, material or workmanship problems, and normal wear and tear.

MIMTAC CORE AR-15 Drop-In Single Stage Trigger - 3.5lb - Flat - PA-CORE-BLK-1
The MIMTAC CORE is a drop-in single-stage flat trigger with a 3.5-pound pull weight, designed for AR-15 and AR-10 platforms. It installs into most mil-spec lower receivers without gunsmithing — drop the cassette into the receiver and tighten the set screws.

The CORE is a self-contained drop-in trigger cassette with a flat-face trigger shoe and a 3.5-pound single-stage pull. The break is crisp with no creep and minimal overtravel. The reset is short and tactile for fast follow-up capability. A built-in mechanical drop safety is integrated into the cassette.

The trigger internals are heat-treated steel housed in a 7075 aluminum cassette body. The combination provides the durability needed for sustained use across range sessions, competition, drills, and duty applications while keeping the overall trigger assembly lightweight. The flat-face lever provides a consistent finger placement and a more predictable pull feel compared to curved trigger designs.

The MIMTAC CORE is compatible with AR-15 and AR-10 lower receivers in 5.56 NATO, .223 Remington, and .308 Winchester. It is designed to work with most mil-spec receiver dimensions. Compatibility with non-mil-spec or proprietary lower receivers should be verified before purchase.

The drop-in cassette design eliminates the need for individual trigger pin, hammer, disconnector, and spring installation. The self-contained unit drops into the receiver as a single assembly.

The CORE suits shooters looking for a single-stage trigger upgrade with a clean break, fast reset, and straightforward installation across AR-15 and AR-10 builds.

MIMTAC manufactures trigger systems and firearm components.