I have done some testing with the XCB bullet coated with Smokes Translucent Copper, water quenched after the bullets were cured applied a gas check and let them sit for a couple weeks to age harden before loading so I know how the load will shoot with the check not coated. I've done several load test and finally settled on 35.0 grs. of H-4198 in the Remington 770 in 30-06.
It's a budget rifle I paid $200 for and it's topped with a fairly cheap but seem to be pretty accurate adjustment wise 4 X 16 X 44 scope. I've only been doing my test in the back yard range at 50 yds. which is as far as I can safely shoot around here due to homes being all around me. I generally find that anything that shoot well at 50 yds. shoot about as well at 100 if I do my part and thats about all I'm looking for, anything else is a bonus. Here is my 5 shot test target I shot a couple weeks ago. I can shoot this group on a regular basis if I do my part.
The closest public range is basically a day trip so I will go there later in the fall where I can access there 250 yd. range and it will be much cooler then. Basically 250 yds. is over kill around here as most hunting or target shooting is done at 100 yds. or less. I'll load up a batch of the same load with the gas check coated and see if they give identical results.
Here is the chrono data to go with the above group.