Quick Tip: Pistol Caliber AR-15 Buffer Weights

Published on April 22, 2020
Duration: 2:36

This video explains the necessity of heavier buffers in pistol caliber AR-15s compared to standard carbine buffers. The increased weight is crucial for blowback-operated systems to slow the bolt's rearward travel, preventing premature ejection and potential malfunctions. The video also touches on how buffer length can be adjusted for specific calibers and reduced bolt travel.

Quick Summary

Pistol caliber AR-15s using blowback operation require heavier buffers (approx. 6-8 oz) than standard AR-15s to slow bolt travel. This prevents premature ejection and malfunctions. Suppressors may necessitate even heavier buffers due to increased back pressure. Buffer length can also be critical for optimal performance.

Chapters

  1. 00:04Introduction to Pistol Caliber Carbine Buffers
  2. 00:19Approximate Buffer Weights by Caliber
  3. 00:44Impact of Suppressors on Buffer Choice
  4. 00:54Why Heavier Buffers Are Needed for Blowback
  5. 01:32Buffer Length and Bolt Travel Considerations
  6. 02:11Conclusion and Further Assistance

Frequently Asked Questions

Why do pistol caliber AR-15s need heavier buffers than standard carbine buffers?

Pistol caliber AR-15s typically use a blowback operating system, which lacks the gas impingement system of standard AR-15s. The heavier buffer is essential to slow down the bolt's rearward travel, preventing premature ejection and potential malfunctions.

What are the approximate buffer weights for common pistol calibers in AR-15s?

For 9mm, expect around 6 ounces. For .40 Cal, around 7 ounces. For .45 ACP and 10mm, buffers are generally around 8 ounces. These weights can vary slightly between manufacturers.

Does running a suppressor affect the buffer weight needed for a pistol caliber carbine?

Yes, running a suppressor on a pistol caliber carbine often requires a slightly heavier buffer. The suppressor increases back pressure, and the heavier buffer helps to manage this extra pressure and ensure reliable cycling.

Can buffer length also be important for pistol caliber carbines?

Yes, buffer length can be important, especially for calibers with shorter case lengths like .45 ACP. Some buffers are designed with longer pads to accommodate the reduced bolt travel required for these cartridges, potentially improving reliability.

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