I'm with powdr, primers will back out on an uncharged case with no powder due to the fact that when fired the powder charge resets the primer as it is pushed back against the bolt face. Had a friend that had rounds that wouldn't fire and it ended up being a dirty (inside) bolt body impeding the firing pin strike. Once cleaned it worked fine. Comparing apples to oranges here but, you want to see primer back out fire some, just primed cases in a revolver. Had a friend do this and the cylinder got where it wouldn't turn without effort. Just my 2 cents worth.
