Mk262 Cloning - pt 5 - Varget

Published on September 19, 2017
Duration: 25:32

This video details the reloading process for cloning Mk262 Mod 1 ammunition, focusing on the use of Varget powder and Remington 7 1/2 primers. The instructor meticulously prepares brass, dispenses and trickles powder, and then tests loads with both Sierra and Nosler bullets. The process highlights the importance of case preparation, primer fit, and the challenges of achieving desired velocities with compressed loads, offering insights into load development for high-performance ammunition.

Quick Summary

When cloning Mk262 ammunition with Varget powder, careful brass preparation is key. Remington 7 1/2 primers are a close match to those found in Black Hills ammo. Load development with Varget in .223/5.56 cases, tested up to 24.5 grains, showed good accuracy with both Sierra and Nosler bullets, though velocities were slightly below target.

Chapters

  1. 00:00Introduction & Primer Issue
  2. 00:31Remington 7 1/2 Primers
  3. 00:48Mk262 Ammunition Goal
  4. 01:13Brass Case Capacity & Primer Fit
  5. 02:17Primer Diameter Differences
  6. 03:26Need for New Brass Batch
  7. 03:40Load Development Strategy
  8. 04:52Brass Preparation Process
  9. 05:48Powder Selection: Varget
  10. 06:04Varget Load Data & Case Capacity
  11. 07:35Primed Cases Ready
  12. 07:41Powder Dispensing Method
  13. 08:11Lyman Gen 6 vs. RCBS Uniflow
  14. 09:23Range Setup & Conditions
  15. 10:07Testing Sierra Bullets (23.3gr)
  16. 10:45Testing Sierra Bullets (23.6gr)
  17. 11:40Testing Sierra Bullets (24.2gr)
  18. 12:17Testing Sierra Bullets (24.5gr)
  19. 13:19Testing Nosler Bullets (23.3gr)
  20. 14:33Testing Nosler Bullets (23.6gr)
  21. 15:02Testing Nosler Bullets (23.9gr)
  22. 15:38Testing Nosler Bullets (24.2gr)
  23. 16:32Testing Nosler Bullets (24.5gr)
  24. 16:40Brass Inspection Post-Firing
  25. 17:26Accuracy Analysis: Best Groups
  26. 18:12Load Selection Difficulty
  27. 18:26Nosler Bullet Performance Verdict
  28. 18:54Velocity Anomalies & SD Numbers
  29. 20:01Max Velocities & Missed Targets
  30. 20:52Next Steps: Primer Comparison
  31. 21:30Primer Close-Up: Remington vs. Black Hills
  32. 22:21Future Powder Candidates
  33. 23:09Requested Powders: TAC & 8208 XBR
  34. 24:05Alternating Video Content
  35. 24:28Next Video Delay & Elk Scouting
  36. 25:13Conclusion & Channel Support

Frequently Asked Questions

What primers are suspected to be used in Black Hills Mk262 ammunition?

Early suspicions suggested Remington 7 1/2 small rifle benchrest primers were used in Black Hills Mk262 ammunition. While the instructor found Remington 7 1/2 primers to be a very close match in appearance and weight, subtle differences remain, leaving some uncertainty about an exact match.

What are the recommended load data ranges for Varget powder in .223/5.56 when cloning Mk262?

For cloning Mk262 with Varget powder in .223/5.56, Hodgdon lists a max charge of 23.7 grains. Nosler's data goes up to 24.0 grains. The instructor tested up to 24.5 grains, finding it compressed but manageable, though exceeding published maximums.

Why is the Lyman Gen 6 powder dispenser preferred for extruded powders?

The Lyman Gen 6 powder dispenser is recommended for extruded powders because they are easier to clean out of the mechanism compared to ball powders. For ball powders, a more traditional measure like the RCBS Uniflow is suggested due to their tendency to throw more consistent charges.

What were the accuracy results when testing Varget powder with Sierra and Nosler bullets for Mk262 cloning?

Testing with Varget powder showed promising accuracy for both bullet types. The best group with Sierra 55gr bullets was .417 inches at 23.6 grains. The Nosler Custom Competition bullets also performed well, with the instructor deeming them a 'shooter' for this application, achieving groups in the .400s to .900s range.

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