I have some previously fired Winchester brass I bought form someone that has a rather significant crimped ring just slightly foreward of halfway up the case that you can see inside the case as well and I have yet to load those because of that. It just looks like a problem waiting to happen.

I have some CBC cases that have a very slight ring on the outside of the case, and not as noticeable inside the case as the Win, right where the base of a 250 XTP sets when seated. I have loaded these with heavy loads several times and they are still going strong.

It just makes me wonder why either of them do that.