MMJ 5.7mm Spitfire Headspace?

[alco3]

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?

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[browningautorifle]

I can't see that you have any choice but to use a drill round made from your dies. Load just the same but no powder or primers. You can take them apart and finish them later. On the bright side you shouldn't have much cartridge stretch.

[shadycon]

Check e-gunparts.com. Cat.#29, pg. 1021. Go #811410-Nogo #811420 price ea. $52.50[ouch] Hope this helps.GK