Had an odd occurrence yesterday when using my 03A3 with the NOE copy of the 311291 and 13 grs of Red Dot. Fired 25 of 50 I had with me and all the primers backed out of the case, some more than others. Have used this load and rifle for years with no issue, probably over 1K rounds. The brass was once fired from a member here and was FL sized in with Hornady dies, tumbled, expanded and loaded. Only difference from past brass processing is the Hornady die, in the past used an RCBS FL die. Expected the brass to fire form to the chamber and then just neck size on subsequent loadings (keep brass for my 06's separate). Think the firing pin blow is pushing the case forward and when fired the case is seizing to the chamber walls and letting powder gas push the primer back to the bolt face. Will clean the chamber before next firing and see if this helps, but otherwise am at a loss to what is happening.