What is "The Quarter Trick"?

Published on October 31, 2025
Duration: 4:33

This video demonstrates a simple, low-cost modification known as 'The Quarter Trick' for AR-15 firearms equipped with .22 conversion kits. The technique involves using a US quarter as a shim within the buffer tube to reduce play in the bolt carrier group, which can often lead to feeding issues with .22LR ammunition due to manufacturing tolerances in milspec AR-15 receivers. This fix aims to improve the reliability of .22 conversion kits by ensuring proper alignment and movement of the BCG.

Quick Summary

The 'Quarter Trick' is a simple DIY gunsmithing technique where a US quarter is used as a shim inside the buffer tube of an AR-15. This helps to reduce play in the bolt carrier group, improving the feeding reliability of .22 conversion kits by addressing variances in milspec receiver tolerances.

Chapters

  1. 00:03Introduction to the Quarter Trick
  2. 00:15Why .22 Conversion Kits Can Be Finicky
  3. 00:34Milspec Tolerances and Their Impact
  4. 00:53Demonstrating the Quarter Trick Fix
  5. 01:34How Play Affects Feeding
  6. 02:22Applying the Quarter as a Shim
  7. 03:05Addressing 'Cheap Copout' Concerns
  8. 03:40Is it Out of Spec?
  9. 04:18Improving Reliability with the Fix
  10. 04:24Conclusion and Safety Reminder

Frequently Asked Questions

What is the 'Quarter Trick' for AR-15 .22 conversion kits?

The 'Quarter Trick' is a simple DIY gunsmithing technique where a US quarter is used as a shim inside the buffer tube of an AR-15. This helps to reduce play in the bolt carrier group, improving the feeding reliability of .22 conversion kits.

Why do AR-15 .22 conversion kits sometimes have feeding issues?

.22 conversion kits can be finicky due to the wide variance in manufacturing tolerances of milspec AR-15 uppers and lowers. Excessive play in the bolt carrier group can prevent it from picking up or feeding rounds correctly.

How do I perform the 'Quarter Trick' on my AR-15?

First, ensure your firearm is unloaded. Remove the bolt carrier group, then place a US quarter in front of the buffer, typically on the buffer retaining pin. Reinstall the BCG, and the quarter will act as a shim to tighten the fit.

Is using a quarter as a shim a reliable fix for .22 conversion kits?

Yes, the 'Quarter Trick' is a widely recognized and effective low-cost solution for improving the feeding reliability of .22 conversion kits. It addresses the common issue of excessive BCG play caused by varying receiver tolerances.

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