7mm-08 Go Gauge for 7mm-08AI?

DoneNOut

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Sent a barrel in to have chambered for 7mm-08AI. They said I could send them a 7mm-08AI go gauge, or they would just use a 7-08 go gauge + .004. What do you think?
 
The Go gauge actually becomes the NO GO gauge.....better clarify that. The AI is actually Shorter than the parent case so it would be Go minus .004. I like Minus .006 to minus .010, and on the minus .010 I run new brass through the full length sizer and bump back. New brass will vary a little on the headspace length.
 
The Go gauge actually becomes the NO GO gauge.....better clarify that. The AI is actually Shorter than the parent case so it would be Go minus .004. I like Minus .006 to minus .010, and on the minus .010 I run new brass through the full length sizer and bump back. New brass will vary a little on the headspace length.
Ok, That is what I was thinking. I will just buy a gauge and send it. My 243AI gauge from Forster worked great in my rifle.
 
Seems to me that a set of gauges would be easy enough for gunsmith/engineer to whip up. If you do use the P.O. Ackley brass method I'd probably pack it with epoxy to ensure that over the years it doesn't get changed through use.
 
Seems like only the new age guys and hobbyists need an Ackley Improved "GO" gage. Using the "GO" for the 'parent cartridge' as the "NO-GO", and then double checking with a virgin piece of brass (of the parent cartridge) to verify 'crush' is all I've needed for the past 31yrs. In this thread I have read .004-.005, .004-.006, and as much as .010 less than "GO" gage of the parent cartridge. 004-.006 as P.O.Ackley said is plenty, and makes up for variations in cartridge case manufacture. The goal is to have the cartridge case supported between the bolt face and the neck/shoulder junction of the chamber. .001 crush would be enough, as the support at the bolt face and neck/shoulder junction is present. That is all that's required, support for fireforming so the case stretches at the front end, and NOT at the head end. I'm in the camp that says more than .001 or .002 because of possible variation in brass. I am a gunsmith school graduate (Montgomery Community College class of '93) and that was what we were taught. The reamer/gage makers hadn't caught on that they could make more money selling a gage that hadn't been needed since Ackley came up with his Improved line of chamberings. Insert the 7mm/08 "GO", and if the bolt handle starts down its path to "closed", remove the gage and insert a virgin piece of 7mm/08 brass and feel the crush. Strip the bolt of its firing pin assembly and plunger ejector (if it has one) before any gaging. Slip the brass/gage under the extractor so it won't give a false 'feel'.
 
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