Have fun with the big bore!

A friend here in town is currently forming brass for her 577 snider. She's getting me off my duff to get the sixteen bore double rifle running.

I had similar dents on two of the first eight rounds through my 500/450BPE3-1/2" Tolley. I've been rather busy since then, don't remember exactly what the charge was, but it was essentially a very low pressure 4831 load through virgin brass. The dents popped out at the next firing and never happened again. No damage to the brass, no signs of the dent after the second load.

--Tinker