MMJ 5.7mm Spitfire Headspace?
Hello again everyone and thanks for all your past advice. I've got a couple new .30 carbine/MMJ 5.7 barrels that I'm going to assemble. I doubt headspace gauges were ever made for this caliber ... at least I've never seen so much as a reference to them, but such is the lot of the wildcat. I've got , a chamber reamer, a finish reamer and a set of RCBS forming and loading dies. It doesn't look like I will need the chamber reamer, just the finish as both MMJ barrels are pretty close as is. I was going to use the go and nogo gauges on a .30 carbine to come up with the ideal headspace for a carbine and then transfer these results to the MMJ build ... now I'm not so sure. I got to thinking that I'm changing the cartridge from headspacing on the case mouth to headspacing on the shoulder. If this is correct then I really have no reference. All that said, what should I headspace a MMJ 5.7mm Spitfire on an USGI receiver/bolt?
