Length of shot string is not totally determined by length of payload in the shell. The longer/taller payload COULD cause a longer shot string, indirectly, by causing more pellets to scrub the bore and be deformed, but length of shot string is determined more than anything else by hardness of the shot used. The harder the shot the shorter the shot string.
So, if the 20 gauge load happened to be loaded with harder shot than the same weight load in the 12 gauge it would be possible for the shot string to be shorter with the taller payload in the 20 than with the shorter payload in the 12.
It is probable that a 1 oz. load of steel in a 20 would have a shorter shot string than a 1 oz. load of lead in a 12, in spite of the taller load in the shell.
Last edited by Stan; 07/21/10 06:13 PM.
