I did have one thought cross my mind. Is it possible a heavier bullet would be more efficient in this scenario?
My thoughts on it are it would be harder to push down the barrel, so that means slower, but at the same time giving the powder more "time" to work on it.
I will state that I am not a believer in faster powder/short barrel theory(to a point). I do firmly believe that powder burns in the first 16 or so inches of a barrel.
