Shooter14854
Member
- Joined
- Jun 9, 2021
- Messages
- 24
Hey everybody I’m hoping somebody here could give me some guidance. I recently got the tools to convert .223/556 brass into 300aac. I’m using the RCBS short base dye for sizing. Trimming the case to 1.360. I’m loading Hornady 150gr HPBT. I measured the neck thickness (only using brass with .013 or lower neck thickness) of every piece of brass after trimming. All of my converted brass is seating perfectly in my Hornady headspace gauge. However when I seat the bullet into the case (2.090 COL) the completed rounds will not sit flush in my headspace gauge. About 95% of them stick out about 1/8th inch. I’ve tried resizing them with the RCBS dye again, a Lee dye and checked if it sat after doing a taper crimp. The round seem to seat fine in my rifle but I havn’t tired firing them yet. I didn’t have any rounds fail to fully seat in the rifle or get stuck.
Additionally, I tried running once fired factory 300 blackout brass through the same dye with the same process as my converted brass. All of the factory brass seats fine in the headspace gauge after the bullet has been seated. I’ve compared the measurements on my converted rounds to my rounds using factory brass and they are virtually identical. I have no idea what to do and am completely out of ideas. Any help would be very appreciated! Thank you all!
Additionally, I tried running once fired factory 300 blackout brass through the same dye with the same process as my converted brass. All of the factory brass seats fine in the headspace gauge after the bullet has been seated. I’ve compared the measurements on my converted rounds to my rounds using factory brass and they are virtually identical. I have no idea what to do and am completely out of ideas. Any help would be very appreciated! Thank you all!
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