Great photos of your issue! So, if the bullets aren't shaved as your photos suggest, and you are using the 18 Brinell, then it looks pretty much like blow by. You may have to slow them down a tad. I've had great success with the MBC Hy Tek, 12 Brinell, in .38 (158 g. SWC) up to +P velocities and in .44 Special (240 g. SWC), but no real magnums. Good luck figuring this out and let us know what you find.

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