Ring around the case

[xjtony]

Oddly none of the other hornaday brass I have (SST, black, or fresh cases have done it. Only the AG.

[Cereal Thriller]

All my hornady brass has it.

it is a very common sight in semi auto cases. Enough of the head has to remain out of the chamber, when the firing of the bullet occurs the shell is moving backwards to be ejected before the bullet leaves the barrel (at least on anything of typical barrel length). You still have pressure in the barrel and the walls of the brass at the point on the shell casing just barely takes a little puff before the shell is pulled clear of the chamber, bullet exits the barrel and pressures are gone. So when you resize you hit this spot and all is well again.


Glock had this issue with an unsupported chamber, would bulge out and leave a smile shape on the brass. Had people worried that if you reloaded the same shell over and over it could possibly cause a failure. I imagine it could if you put serious effort into reloading it and ensuring the shell chambered at the exact place each time.