doublegunshop.com - home Forums General Discussion DoubleGun BBS @ doublegunshop.com Question on Wall Thickness Gage

I can well appreciate David's experimenting with different ideas and styles of measuring instruments - good ideas are worth playing with and David's prototype is very interesting.

I've been less daring and stuck with a more conventional design:





with the ball brazed to the end of the rod. I also made a wooden case that holds this and two bore-gauges and I can take them to gun shows. Portability is a big "plus" and I've never been refused permission to measure wall thickness or bore at any show.

Altho I usually use the device hand-held and horizontal, I can clamp the block in a vise with the rods vertical and lower the barrels over the ball-end. Never tried suspending it.

Gnomon, I made one similar to yours also. For the ball I drilled and put a 3/8" ball bearing near the end. I use mine vertically and put the spring under the bar to keep that barrel away from it. This came from the late Dr.Oscar Gaddy.

It is adjustable in length, and I can do barrels all the way to choke, I usually set it at 18".

Thanks to all, and Berrien, I haven't given up yet.
The Hosford Gage looks like the easiest one to use and have the abiltiy to be repeatable every time. There is no weight on the rod to affect readings. The more you use this gage the easier it becomes to guide it parallel to the barrel.

Nice!
But I don't understand where the spring goes - can you explain please?

The spring compresses when the barrel is placed on the rod to keep the ball bearing against the barrels ID so that you get a good reading on the OD.

Aha! I see it now. Clever.