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