Originally Posted by
tazman
That was the design right there.
You could also use some thick rubber from an old inner tube shim the rings to the barrel if you like. Might add a little extra vibration dampening to the system as well as keep it from marring the barrel.
If you can grind a groove or beveled edge into some flat stock, as you suggested, that would work as well. That would make a connection that didn't ruin anything that is usable for something else.
I don't know what you have on hand or your skills other than your shooting. I was trying for a simple to make design. If you are like me, you have old rings and maybe some bases around from old setups.
My father ran an auto salvage for years while I was growing up. Lots of times, we had to make do with what we had on hand.
We once designed and built a swiveling boom and winch setup to lift engine blocks into the back of a pickup truck using only parts from cars except for the winch. We used the hand winch from an old wrecker for that.
A cutting torch and a stick welder did the job. Took us about 15 minutes of thought with paper&pencil to design and about two or three hours to build. Worked like a champ.
Before that, I had to load the engine blocks into the truck bed by myself. Necessity being the mother of invention and all.
We did stuff like that all the time.