Yes, I guess it would have been more accurate to say the split was just above the web. When I say the base was fine, I meant no pressure signs: The primer was not flattened, there were no bolt face marks, etc. A friend was looking for an ejector mark, but I reminded him this is controlled round feed.

Here is what I learned today: I pulled the last bullet and am soaking the primer. When I pulled the bullet, what I learned was these cases were filled with cordite. Not sure if that has weakened the brass over time, or something else, but it does explain the difference in felt recoil compared to the Dorfner rounds.

As far as the headspace measurement, I'm not normally a fan of the "tape" method, but in this case, with (measured) .002 tape, One would close, two would close with some effort, and 3 would close only with great force. So call it somewhere around .004, give or take. That was with the unfired round. Using fired brass, I could get one more piece of tape in, possibly two (how does one actually measure the force of closing the bolt?).