CZ Bren 2Ms 7.62x39 Stovepipes: Cause and possible solutions.

Published on November 9, 2020
Duration: 21:05

This video diagnoses frequent stovepipe malfunctions in the CZ Bren 2Ms chambered in 7.62x39mm. Analysis using high-speed cameras reveals the platform is significantly over-gassed, leading to excessive bolt carrier velocity and timing issues that trap spent casings. While modifying the gas plug can help, CZ is still investigating the root cause of this discrepancy compared to 5.56 variants.

Quick Summary

The CZ Bren 2Ms in 7.62x39mm frequently experiences stovepipe malfunctions due to being significantly over-gassed. This leads to excessive bolt carrier velocity, causing spent casings to be trapped by the returning bolt. While modifying the gas plug can help, users should contact CZ for warranty service rather than attempting DIY fixes.

Chapters

  1. 00:00Intro: CZ Bren 2Ms 7.62x39 Malfunctions
  2. 01:50Range Test: Over-Gassing and Ejection Issues
  3. 04:16Mechanical Comparison: Bren 2 vs SCAR vs ACR
  4. 06:35Gas System & Bolt Velocity Analysis
  5. 09:01Data Summary: Gas Plug Modifications
  6. 13:36Testing Modified Gas Plugs
  7. 17:42Conclusion & Recommendations for CZ Bren 2 Owners

Frequently Asked Questions

What causes stovepipe malfunctions in the CZ Bren 2Ms 7.62x39?

The primary cause identified is the firearm being significantly over-gassed. This leads to excessive bolt carrier velocity, preventing the extractor and ejector from reliably clearing the spent casing before the bolt returns forward, trapping the case.

How does the gas system of the CZ Bren 2Ms 7.62x39 contribute to malfunctions?

The 7.62x39mm variants appear to be over-gassed, even on their standard setting. This results in erratic ejection patterns where spent cases are thrown forward, increasing the likelihood of them getting caught and causing a stovepipe.

Are there any potential solutions for CZ Bren 2Ms 7.62x39 stovepipes?

Modifying the gas plug by drilling a smaller port has shown promise in slowing the bolt carrier and improving ejection timing. However, users are advised not to attempt DIY modifications and to contact CZ for warranty service.

What is the difference between the CZ Bren 2 and the FN SCAR regarding malfunctions?

While often compared, the Bren 2 shares more mechanical traits with the ACR, specifically its short bolt travel. This short window for ejection, combined with over-gassing in the 7.62x39mm variant, makes it more susceptible to timing-related malfunctions than the SCAR.

More Reviews Videos You Might Like

More from Military Arms Channel

View all →