Joe90 has accurately summed it up, and Longshot's suggestion of alchemy pretty much matches my own thoughts. I have often said that successful gunsmiths are also alchemists! The ability to 'create honey out of dogshit' as one of my mates was fond of saying. My opinion on the current subject is that the 6" barrel shortening has reduced the velocity below the 'sweet spot' for the particular projectile. Find a load with a slightly faster powder to boost the velocity by 150-250 fps in the shorter barrel.
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