You guys did should a good job on my last poblem, I thought I might share an experience that I still don't understand. My first "big bore" rifle was a 7mm Rem Rolling Block. I didn't like it and I sold it. A few years ago I bought two 7mm RRB's to play with. I made one into a hunter ala de Haas. I fit the barrel to the receiver with essentially zero clearance between case head and block. No headspace problem at all (finish reamed it myself). I buy two boxes of 7mm commercial ammo. No problems, good accuracy. When I reloaded these cases, I noticed a lot of case stretch. Had to full length resize and trim more than normal for a single firing. Out come the GO/NO_GO's. No headspace problem with very minimal headspace. Trimmed the once fired cases and loaded them up.

Ist handload, which was relatively mild, the case head blows off and hits me in the forehead right above my left eye so hard I was stunned - cut to the skull, blood everywhere - wife freaking out. I thought the RRB had blown up. Nope. It was in fine shape with minimal headspace. I put the rifle in the safe and left it for a year. Recently I pulled it out, and tried handloads again. Every reloaded case parts or begins to part, but none have exited the rifle has did the first one. I can only use new brass in this rifle.

The loads are 3 grs from published max, so pressure is not the problem. My question is: How did that case head come out of the block? A 0.001" feeler gauge won't slide between the case head and the block and there are no signs of excessive pressure whatsoever.

My question for those familiar with RRB is how did that case head exit that receiver block without damaging the receiver? I thought the RRB's were case hardened. A RRB locks up tight as a drum.

My take is that only new brass can be used once, as the case stretches so much that a second loading results in a separated case head. How can there be that much spring in a case hardened rifle reciever? The case head that hit me fell into my shirt pocket after it hit me in the head and it is about 1/4" long. The remaining case easily came out with a tap with no sticking evident.

Any ideas? I have pondered this for two years, and I find it very suspicious.

Jim.
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