are all calipers the same?

[Chas1]

nathank, once you get them you can do a rough check by taking the known diameter of your rifle muzzle and see how close they are unless you have some ceramic or other type of instrument calibration blocks. at least you'll know whether your in the ballpark. Let us know how you like them. Enjoy.

 

[boomtube]

I might as well start with the 15 dollor master craft with a lifetime warrenty for free using a gift certificate and save up for a better one down the road by the sounds of it.

That's a good move. And, if you wait until you actuaqlly have a failure you are unlikely to ever need a replacement. Unless you drop it, in which case it won't matter how much you paid for it.