Rosco Manufacturing - 26,750 Rounds of Full Auto - Barrel Autopsy

Published on April 23, 2020
Duration: 17:12

This guide details a comprehensive barrel autopsy performed by Chad Albrecht of the School of the American Rifle. It covers the methodology for inspecting a Rosco Manufacturing 10.5-inch Nitride barrel after 26,750 rounds of full-auto fire, focusing on identifying wear points like muzzle erosion, throat erosion, and gas port wear that impact accuracy. The process utilizes specialized gauging tools for objective analysis.

Quick Summary

Severe muzzle erosion was the primary factor causing accuracy degradation in a Rosco Manufacturing 10.5" Nitride barrel after 26,750 full-auto rounds. While throat and headspace remained within spec, the muzzle wear was significant enough to cause keyholing, highlighting the importance of specialized gauging for barrel assessment.

Chapters

  1. 00:00Introduction & Background
  2. 00:50Inspection Methodology
  3. 02:05Visual Inspection & Markings
  4. 03:15Borescope Analysis
  5. 07:40Gas Port & Barrel Length
  6. 09:30Muzzle Erosion & Accuracy Failure
  7. 10:05Throat Erosion & Headspace
  8. 12:00Straightness & Thread Concentricity
  9. 13:30Final Assessment

Frequently Asked Questions

What was the primary cause of accuracy loss in the Rosco Manufacturing barrel after 26,750 full-auto rounds?

The primary cause of accuracy loss was severe muzzle erosion. A muzzle erosion gauge showed significant wear, allowing it to sink deep into the bore, which directly impacts projectile stability and accuracy.

How was the gas port wear assessed on the Rosco Manufacturing barrel?

Gas port wear was assessed using precision pin gauges. The port was measured at 0.072 inches, and visual inspection revealed substantial erosion, particularly on the side facing the muzzle, a common issue in high-round-count barrels.

What specialized tools are used in a barrel autopsy like the one performed on the Rosco Manufacturing barrel?

Specialized tools include a borescope for internal inspection, precision pin gauges for gas port measurement, muzzle and throat erosion gauges, barrel straightness gauges, and thread concentricity gauges for comprehensive wear analysis.

What was the condition of the throat and headspace on the Rosco Manufacturing barrel after extensive full-auto use?

Remarkably, the throat erosion was measured at level 4 (out of 11), and the headspace was well within safe specifications, not even closing on a 'no-go' gauge, indicating good longevity in these areas.

Related News

All News →

More Gunsmithing & DIY Videos You Might Like

More from School of the American Rifle

View all →