I want to see yours... what can I say, I'm hot for them.

I started a string a couple of months ago asking where I could get a mil spec go gauge, and to my disappointment they seem to be next to impossible to get.  I have a Colt spec (mil spec) field guage, it looks about the same as the Forster guages.  

I would think that someone would be able to make a decent amount of coin selling mil spec go & field guages, I just can't believe no one does it for the civilian market.

You can buy military Field Gauges from places like Fulton Armory - complete in thier foil with a calibration card.

There are no 'go' gauges at Unit or Direct Support maintenance levels - I've never seen one mentioned in a TM, but Tweak has indicated they exist at higher levels (Depot or Arsenal level perhaps?).

Don't worry about the go Gauge, all you need is a field gauge if you are buying quality parts (i.e. Colt or Bushmaster).

Even if building from new parts you would be wise to also have a go gage,   I have measured various
new bolts and there is a .003 variance in lug size.   Certain bolt / barrel combos will be .001 shy of closing on a go gage which may cause higher than normal chamber pressures.