I am having an issue with loads I have been working on for a Ruger MII .223 rifle 22 inch barrel. I can get great groups only after I shoot the first shot which normally is about 1.0 to 1.5 inches high depending on which load I am using. The other shots after the first group around .5 inches at 100 yards. I have floated the barrel, cleaned the barrel, changed bullets until I am out of ideas. I am using Accurate 2460 - 24 to 24.5 Gr works best, Hornady V-Max 52 Gr, Remington 55 Gr SP, Speer 50 Gr Spitzer and CT 55 Gr Ballistic Silvertip. All do the same thing - the Remington and the Speer seem to open up a little more than the others. Anyone seen this before?