300 BLK - Powder Coated Bullets With IMR-4227

Published on March 8, 2017
Duration: 11:15

This video details the testing of IMR 4227 powder for 300 Blackout reloads using powder-coated bullets. The instructor experienced issues with powder-coated bullets in previous tests and aimed to determine if IMR 4227 would function reliably. Two bullet weights were tested: 160-grain and 202-grain, with specific powder charges and overall lengths outlined. The testing involved both unsuppressed and suppressed firing, with observations on cycling, bolt lock-back, and accuracy.

Quick Summary

IMR 4227 powder was tested in 300 Blackout with powder-coated bullets, using 15.5 grains for 160gr bullets and 9.5 grains for 202gr bullets. CCI No. 41 primers were used. Suppressors significantly improved cycling performance, especially for subsonic loads.

Chapters

  1. 00:01Introduction: Testing IMR 4227 with Powder Coated Bullets
  2. 00:40Load Data: 160gr and 202gr Bullets
  3. 01:38Primer Selection: CCI No. 41
  4. 03:40Unsuppressed Testing: 160gr Bullets
  5. 04:24Unsuppressed Testing: 202gr Bullets
  6. 04:53Initial Cycling Observations
  7. 05:08Suppressed Testing: 202gr Bullets
  8. 05:48Target Engagement: 90 Yard Plate
  9. 06:14Target Engagement: 50-60 Yard Plate
  10. 06:40Bolt Lock Back Observation
  11. 06:50Supersonic Load Testing
  12. 08:10Subsonic Load Testing with Suppressor
  13. 08:16Aiming with Subsonics on 90 Yard Plate
  14. 08:54Swinging Plates with Subsonics
  15. 10:16Conclusion: IMR 4227 Performance
  16. 10:25Future Powder Testing

Frequently Asked Questions

What powder charge was used for 160-grain powder-coated 300 Blackout bullets with IMR 4227?

For 160-grain powder-coated bullets in 300 Blackout, the tested load using IMR 4227 was 15.5 grains. The overall cartridge length was maintained at 2.35 inches for optimal function.

What is the recommended load for 202-grain powder-coated 300 Blackout bullets using IMR 4227?

When reloading 300 Blackout with 202-grain powder-coated bullets and IMR 4227, a charge of 9.5 grains was used. The overall length for these cartridges was set at 2.1 inches.

How does a suppressor affect the cycling of 300 Blackout loads with IMR 4227?

The video demonstrates that a suppressor significantly improves the cycling and bolt lock-back performance of 300 Blackout loads, especially with subsonic charges, which initially showed some cycling issues when unsuppressed.

What primers are recommended for 300 Blackout reloads with IMR 4227?

The instructor utilized CCI No. 41 primers for all tested 300 Blackout loads featuring IMR 4227 powder and powder-coated bullets. This primer is often chosen for its reliability and suitability for AR-style platforms.

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