How do you read a CMP muzzle gauge

[marks]

I just purchased a new CMP muzzle gauge (the one that looks like a bullet) and I'm not sure how to read the damn thing. It has a machined flat space that has 4 horizontal marks and the numbers "0" and "2" engraved in the flat space. I have a CMP special that reads just above the first line but after that I'm confused. Do the horizontal lines indicate a +1 or a +.5. The gauge didn't come with any paperwork (except the invoice):).

Thanks,

Mark

[jbkf1003]

I don't have one but if it's what they guage their service grades on, If it reads just shy of 1 it's a zero. If it reads a 3 it's really a 2+. :)

[musketjon]

You'd be better served by using machinist's gage pins. They're infinitely more accurate and take all of the guess work out of the equation and they only cost a couple of bucks a piece.
Jon

[jak]

The line going around the gauge that bisects the "0" is zero or .300" or 30 caliber. The line going around the gauge that bisect the "2" is two or .302".
The line going around the gauge between the "0" and the "2" is obviously "1" or .301".

[seaninmich]

You'd be better served by using machinist's gage pins. They're infinitely more accurate and take all of the guess work out of the equation and they only cost a couple of bucks a piece.
Jon


that, and the CMP gauge is crap. how can you expect to take an accurate measurement when there is one flat side? every time you rotate the gauge it reads differently. plus, i found the cmp gauge wears rapidly. there is a reason the hang tags read "2+" or "4=". they cant get any more accurate than that

[Old Guard]

that, and the CMP gauge is crap. how can you expect to take an accurate measurement when there is one flat side? every time you rotate the gauge it reads differently. plus, i found the cmp gauge wears rapidly. there is a reason the hang tags read "2+" or "4=". they cant get any more accurate than that

Haaaa, Someone else is not real tickled with the aluminum guage that cmp is selling?? I have it and read it with the calipers, plus used it beside an M2 round..I believe i wasted my money on it..You have to be very GENTLE with it when placing into the barrel? I am still working on a Breech guage to read the setback(TE) there? But lately been distracted with my Mosins...Don't have time to do them both..?

[Roadkingtrax]

I still use my steel Stone Ax combo gauge, its merely a guide anyway. The proof is in the shooting, and it will get you close to barrel numbers. Seen a few rifles sold with "1" on the muzzle, and crown looked like dog crap.