OK, I finally got around to bussin some caps today....... it kind of sucked, but I'm narrowing my problems down. I shot 40 rounds, all with once fired, once neck sized Remington brass, 220 grain Sierra Match Kings, and OAL was 2.26o inches. Ruger American Ranch, with 16.5 inch barrel.
9.2 grains of Winchester 296 was in the 890 fps range...... TERRIBLE vertical string, horizontal OK.
8.2 grains of Winchester 296 was in the 775 fps range..... TERRIBLE vertical string, horizontal OK.
12.2 grains of CFE-BLK was in the 940 fps range..... and gave me the best groups....
In my notes I recorded 2" groups with CFE-BLK and 208 grain Amax bullets..... but of course I didn't note the charge...... (bonehead).
All indication show I have plenty of room to experiment with upping the charge and I will probably work on getting the bullet a little closer to the lands, I don't mind loading one round at a time.
Suppressed or unsuppressed, made no difference in my groups.... I'm almost positive my ridiculous vertical strings are related to resting the fore end of the stock on the front bag, while I bury my weight on the cheek rest which also puts weight on the stock which rests in a rear sandbag. The CFE groups, I changed it up with a front bag only, with the sandbag under the action (just in front of the magazine), and my groups improved.... but not where I wanted.
Please feel free to give me a hard time on this one!!