I broke out the machinist tools and took some measurements.
The bore on the RH is 0.4509" and the SRH is 0.4515".
The cylinder bores on the RH are consistent at 0.4509 and the SRH is 0.4516.
The lead I was shooting today all came in around .452 so that shouldn't be too much of a problem.
The cylinder gap on the RH is .0045" minimum and .0085" at maximum. That gives me .004" in thrust.
Cylinder shake seems to be the same between both guns but I didn't set up a fixture to measure it.
Both barrels have similar crowns.
If there' s a mechanical issues I'm not sure what it is.
I guess I'll load up more test rounds and let a friend fiddle with it.
I've got some .451 and .452 jacketed stuff from 185 through 300 to run next time around.