Why you should avoid Aluminum AR15 Gas Blocks

Published on October 13, 2020
Duration: 2:46

This guide explains why aluminum AR-15 gas blocks should be avoided due to their susceptibility to erosion and loosening caused by thermal expansion differences with barrel steel. The instructor demonstrates how aluminum blocks can become sloppy, leak gas, and erode over time, recommending steel or titanium alternatives for most applications, especially those involving higher round counts or rapid fire.

Quick Summary

Aluminum AR-15 gas blocks are not recommended for most applications due to their tendency to erode and loosen. This occurs because aluminum expands and contracts at different rates than barrel steel, leading to gas leaks and a sloppy fit, especially under heavy use or rapid fire.

Chapters

  1. 00:00Introduction to Gas Block Materials
  2. 00:03Risks of Aluminum Gas Blocks
  3. 00:17Examples of Aluminum Gas Blocks
  4. 00:49Heavily Used Aluminum Gas Block Erosion
  5. 01:23Thermal Expansion Issues
  6. 01:32Recommendations: Avoid Aluminum
  7. 01:47Durable Material Alternatives
  8. 01:59Conclusion and Thanks

Frequently Asked Questions

Why should I avoid aluminum AR-15 gas blocks?

Aluminum gas blocks should be avoided because they erode and loosen due to the difference in thermal expansion between aluminum and barrel steel. This can lead to gas leaks, sloppy fit, and compromised firearm function, especially under heavy use.

What problems can occur with aluminum AR-15 gas blocks?

Aluminum gas blocks can erode around the gas port and gas tube interface, leading to a sloppy fit and gas leaks. They also expand and contract at different rates than barrel steel, causing them to loosen during firing.

What materials are better for AR-15 gas blocks than aluminum?

For AR-15 gas blocks, it is recommended to use materials like stainless steel, regular steel, or titanium. These materials offer greater durability and resistance to thermal expansion issues compared to aluminum.

When might an aluminum AR-15 gas block be acceptable?

An aluminum gas block might be acceptable only for AR-15s with very low round counts, intended strictly for paper punching or slow-cadence target practice. For any regular or demanding use, they are not recommended.

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