I'm getting ready to put on my .338-06 barrel and dont have any headspace gauges and I've always used fl sized brass in the past, but I havent received my .338-06 dies from midway yet and was wondering if I can use fl sized .30-06 brass for a headspacing gauge? The reason I'm curious is there is 1 go-gauges for for all the 06 calibers, so I figured brass would be the same. Any help is appreciated, thanks.