Quick Tip: Why the Mag Won't Lock in Your AR-15

Published on December 23, 2020
Duration: 3:10

This video addresses why an AR-15 magazine may not lock in, highlighting issues like receiver/catch defects, high spring tension in new magazines, bolt drag, and debris under the magazine catch. It offers practical solutions including applying firm pressure, testing with the bolt locked back, breaking in new magazines, and regular cleaning.

Quick Summary

New 30-round AR-15 magazines often have high spring tension, requiring a firm push to lock when the bolt is closed. Testing with the bolt locked back can confirm if spring tension is the cause. Debris under the magazine catch can also prevent proper seating.

Chapters

  1. 00:00Intro: Mag Not Locking Issues
  2. 00:20Receiver & Catch Defects
  3. 00:41High Spring Tension Fix
  4. 01:25Bolt Drag & Break-in
  5. 02:18Debris & Maintenance

Frequently Asked Questions

Why might a new AR-15 magazine be difficult to lock in?

New 30-round AR-15 magazines often have high spring tension. This requires a firmer push to engage the magazine catch, especially when the bolt is closed. Testing with the bolt locked back can confirm if spring tension is the primary issue.

What is bolt drag and how does it affect magazine insertion?

Bolt drag occurs when the bolt carrier group interferes with the top lips of the magazine. Checking for this on an empty magazine can indicate potential fitment problems or the need to break in the magazine through use or by leaving it loaded.

How can debris cause an AR-15 magazine to not lock?

Dirt, grime, or other debris can accumulate under the magazine catch. This buildup prevents the catch from fully rising or seating properly, which is necessary for the magazine to lock securely into the receiver.

What are potential manufacturing issues that prevent AR-15 magazine lock-up?

Improperly manufactured lower receivers or magazine catches can cause issues. Defects in these components might prevent the magazine catch from engaging correctly with the magazine's catch lug, leading to failure to lock.

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