Loading 300 Blackout - ep 2 - First loading and function testing

Published on September 5, 2015
Duration: 23:56

This video details the process of preparing previously formed 300 Blackout brass for reloading. It covers essential steps like sizing, trimming to precise lengths, deburring, sorting brass by weight, and priming. The instructor emphasizes treating the brass as if it were new, ensuring proper dimensions and consistency for reliable ammunition.

Quick Summary

Reloading 300 Blackout brass involves treating it like new, including full-length sizing and trimming. Leaving a slight extra length during the first trim allows for a second pass to ensure a square case mouth. Sorting brass by weight is crucial for consistency, and a starting load of 14 grains of Winchester 296 is often used with 150-grain bullets.

Chapters

  1. 00:00Introduction to Reloading 300 Blackout Brass
  2. 00:53Sizing the Formed Brass
  3. 01:49Checking Case Length After Sizing
  4. 02:44Second Sizing Pass and Trimming Prep
  5. 04:24Trimming and Deburring Cases
  6. 04:41Sorting Brass by Weight
  7. 06:04Neck Thickness Considerations
  8. 06:33Reviewing Case Dimensions
  9. 08:29Priming the Cases
  10. 09:04Powder Charging for 300 Blackout
  11. 11:32Setting Up the Seating Die (Lee)
  12. 14:25Switching to Forster Seating Die
  13. 18:15Adjusting Seating Depth and OAL
  14. 19:15Pulling Bullets to Check Tension
  15. 20:28Re-priming and Preparing for Function Test
  16. 20:35Function Testing the Reloaded Rounds
  17. 21:09Inspecting Fired Brass
  18. 22:35Comparing Fire-Formed vs. Unfired Brass
  19. 23:26Conclusion and Next Steps

Frequently Asked Questions

What is the recommended process for sizing newly formed 300 Blackout brass?

It's recommended to treat newly formed 300 Blackout brass as if it were brand new. This involves full-length sizing, even if the dies weren't fully engaged during the initial forming process. A common setup for the sizing die is to screw it down until it touches the case, then add an additional quarter turn for a proper 'cam over'.

How should 300 Blackout brass be trimmed after sizing?

After sizing, brass should be trimmed to the desired length. It's often beneficial to leave a small amount of extra length during the first trim, allowing for a second pass to achieve a perfectly square and clean case mouth. Deburring the case mouth is also a crucial step after trimming.

Why is sorting 300 Blackout brass by weight important?

Sorting 300 Blackout brass by weight is essential for ensuring consistency in your reloaded ammunition. By discarding cases that fall outside a specific weight range, you create a more uniform batch, which can lead to more predictable performance and accuracy when fired.

What is a common starting powder charge for 300 Blackout with 150-grain bullets?

For 300 Blackout cartridges loaded with 150-grain bullets, a common starting load is 14 grains of Winchester 296 powder. This charge is often used to ensure adequate pressure for proper function and fire-forming without being excessive.

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