So I've never had this happen before or even heard of it... I was getting ready to seat some bullets in my 6.5-06 AI. I don't have an OAL gauge so I graphited the crap out of the inside of the neck, seated a bullet close to what I thought the OAL is, chambered it and closed the bolt. The case was uncharged but it was primed. I put the case in my bullet puller hammer and started hitting away on the garage floor. After about three swings, POW! The primer went off. Anyone experienced this before? It really scared the crap out of me because I had just knocked about eight 338WM that were charged. Thanks in advance.