Hi, David, thanks for your reply. The copper bushing doesn't back out, I have tried this repeatedly. Additionally the primer pocket seems to remain tight even after 5 reloads. I had the same concerns from the get go so I tested these things before bringing this method forward.
The ball bearing trick won't work on steel cases, at least not without exerting more force than I am able to apply. I would try it for sure if I had brass berdan cases.
I saw that posting by Larry Gibson and had tried it without success. No matter how straight I drilled the primer it would always crumple up when swaged. Once I got pretty close but the resulting pocket was way too loose? That was when I decided to figure out another way.
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