AR-15 Bolt Catch — Mil-Spec Style, Precision Machined | UPC 859819007423

Reliable lock-back starts here. The AR-15 Bolt Catch is the small but critical control that locks the bolt open on an empty magazine and lets you release it cleanly after a mag change. Precision machined to mil-spec geometry and built from durable steel with a wear-resistant finish, this drop-in replacement restores crisp, positive function on carbines that are failing to lock back—or upgrades a new build with duty-ready parts you can trust.

Why Upgrade Your Bolt Catch?

• Consistent last-round lock-back: Correct geometry and spring tension interface with standard followers to hold the bolt open every time the magazine runs dry.

• Positive, tactile engagement: Deeply serrated paddle gives your thumb or support-hand a sure, non-slip press during reloads—wet or gloved.

• Mil-spec compatibility: Designed for AR-15/M4 pattern lowers, this catch works with standard bolt catch roll pins, detents, and springs.

• Hardened steel construction: Resists peening and edge wear from high round counts and aggressive training cycles.

• Clean, corrosion-resistant finish: Uniform coating shrugs off carbon, solvent, and sweat for long service life and easy cleaning.

Ideal For

• New builds & part kits seeking proven mil-spec controls

• Refresh/repair of rifles that no longer lock back reliably

• High-volume training guns that demand crisp, repeatable bolt operation

• Duty & defensive carbines where positive manipulation matters

Key Features at a Glance

• Platform: AR-15 / M4 pattern lower receivers

• Function: Locks bolt to rear on empty mag; manual bolt release

• Material: Hardened steel

• Finish: Wear- and corrosion-resistant coating (matte)

• Control Surface: Serrated, easy-to-index paddle

• UPC: 859819007423

Compatibility Note: Fits mil-spec AR-15 lowers. Not for AR-10/.308 receivers (those use different geometry). Works with standard bolt catch roll pin, plunger, and spring.

Installation (Quick Guide)

1. Unload & clear the firearm. Separate upper and lower.

2. Prep the area: Support the receiver to protect the ears around the bolt catch slot.

3. Install plunger & spring: Drop into the bolt catch recess.

4. Align & pin: Position the bolt catch; drive the roll pin from rear to front using a starter punch, then flush with a roll pin punch.

5. Function check: With an empty magazine inserted, pull the charging handle to verify last-round lock-back. Press the paddle to confirm smooth release.

Pro Tip: A drop of oil on the plunger spring and a dab of tape on the receiver can prevent scuffs during installation.

Common Signs You Need a New Bolt Catch

• Bolt fails to stay open on empty magazines (with multiple mags tested)

• Mushy or inconsistent feel when pressing the catch

• Visible rounding/peening of the catch’s engagement surfaces

• Sluggish movement due to corrosion or finish wear

Maintenance & Care

• Wipe carbon from the engagement face during regular cleanings.

• Add a tiny drop of oil to the plunger/spring area to keep movement smooth.

• Inspect the roll pin for drift after hard-use days; re-seat if necessary.

Specifications

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Small part, big reliability—install this AR-15 Bolt Catch to restore crisp lock-back and fast, confident bolt releases in every reload cycle.
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