doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Barrel Caliper?

Has anyone had experience with a "barrel caliper" as shown in Brownell's? I have everything covered with my Skeet's set except .410. For the very infrequent times I need or want to measure a .410, maybe I could make one of these. Whattya think?
TIA
I also have what I believe is called a snap gauge but the legs are not quite long enough to be sure of reaching the bore, behind the beginning of the choke taper(mine reaches about 2-1/2" in) Could I make the legs longer and then somehow correct the readings?
TIA #2

Bore reader update: On good friend Chuck's suggestion, I bought an internal caliper from MSC. It measures from .375" to something over 1.5". The legs are 3-1/4" long. Unfortunately, it was not usable for me. In a .375" hole, the dial reads "0", not .375". Worse yet, the 3-1/4" legs are tapered out, toward the dial end and will only go about 1-1/4" into a .375" hole, where they stick at the "knees". I have a good, old German dial caliper that will not go in far enough either but If I make the legs twice as long on it, then I can calculate what it reads by doubling or dividing what the dial says, at no cost. (I like that)
Thank you,

The legs are tapered because they need the added stability to avoid bending. I have ground the legs on such calipers until they fit into the hole. However, to fit in a .410 bore, they have to be ground pretty thin. I still like using the "small hole gauge". It is a pain, but it gives accurate, repeatable readings, and does not bend or flex.

Jim
Sorry it didn't work out. The brand I stumbled upon works well enough for a 410. Ill try to get you specifics when I get home.