07-22-2018, 01:26 AM
Mad Charlie Wrote:The Hornady tool is only a comparator, not meant for absolute measurement. It is good to have a headspace guage to zero from, (a standard) that is what I do with my .308's.
As long as you are using the same calipers, and same bushing, you should get very usable dimensions. Also depends on how consistent your "touch" is, but as long as one doesn't try to use calipers for a monkey wrench they should be within .001-.002. Won't get much better with calipers.
Yeah, but the comparison to SAAMI spec is an important one since I'm on the fringe (I don't care about LBC spec - the 1.225 was probably for legal reasons, an inside joke or a combination thereof). Having the NAPA caliper give me a lower reading made me feel better - and that caliper gives me a much "firmer" reading. I'm hoping to get a few rounds through it Monday with the GB bolt, my JP bolt and my old bolt that Midway sold with the Stoner/Satern barrel. My guess is the JP will pull it in .001 or 0.002 and that the headspace is a few thousandths inside spec. I'll just be using 95 gr VMax's I had lying around loaded light. Then I can start convincing myself that the 1.230 outside spec dimension leaves room for tolerance stacking instrument error on top of that. I might be being a bit anal, but it's probably a common side effect from having a barrel blow up in one's face.
Let's go Brandon!