M855A1 Accuracy Test

Published on March 28, 2021
Duration: 22:19

This video tests the accuracy of the military M855A1 5.56mm ammunition across three different AR-15 platforms: a 16-inch Colt LE6920, an 18-inch White Oak Armament barrel, and a 20-inch White Oak Armament barrel. The M855A1 is characterized as a lead-free, steel-penetrator round designed to replace the M855. The testing focused purely on accuracy at 100 yards, with the 18-inch barrel showing the most promising results, while the 16-inch and 20-inch barrels exhibited less consistent accuracy.

Quick Summary

The M855A1 is a lead-free, 5.56x45mm NATO military round adopted in 2010, featuring a steel penetrator tip. Accuracy tests showed varied performance across different AR-15 barrels, with an 18-inch 1:7 twist barrel achieving the best results, while 16-inch and 20-inch barrels exhibited less consistent groups.

Chapters

  1. 00:01Introduction to M855A1 Ammunition
  2. 00:11M855A1 vs M855 Comparison
  3. 01:44Focus on Accuracy Testing
  4. 02:14Introducing Test Firearms
  5. 02:2616-inch Colt LE6920 Setup
  6. 03:0018-inch Ballistic Advantage Upper
  7. 03:3620-inch White Oak Armament Upper
  8. 04:06Pre-Test Barrel Familiarization
  9. 07:55Shooting the 16-inch Colt LE6920
  10. 12:00Shooting the 18-inch White Oak Armament Barrel
  11. 14:33Shooting the 20-inch White Oak Armament Barrel
  12. 18:17Review of Accuracy Targets
  13. 19:43Future Plans for M855A1 Components
  14. 21:04Feed Ramp Concerns with M855A1
  15. 21:29Velocity Data Summary
  16. 21:56Conclusion and Next Video Preview

Frequently Asked Questions

What is the M855A1 ammunition?

The M855A1 is a lead-free, 5.56x45mm NATO military round adopted by the U.S. in 2010. It features a copper jacket, a lead-free core, and an exposed steel penetrator tip, designed to replace the older M855 round.

How did the M855A1 perform in accuracy tests?

Accuracy varied significantly by barrel. The 18-inch White Oak Armament barrel achieved the best results with M855A1, while the 16-inch Colt and 20-inch White Oak barrels showed less consistent groups, with the 20-inch barrel performing particularly poorly.

What are the key differences between M855A1 and M855?

The M855A1 is lead-free and designed for more consistent terminal performance without relying on tumbling. It also uses powder better suited for shorter barrels and is claimed to be more accurate than the M855, which has a lead core and a steel penetrator inside a closed tip.

What barrel lengths and twist rates were tested with M855A1?

The test included a 16-inch barrel with a 1:7 twist, an 18-inch barrel with a 1:7 twist, and a 20-inch barrel with a 1:8 twist. The 18-inch barrel with the 1:7 twist yielded the most promising accuracy results.

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