I agree with shooting different rounds through different chokes and see how they pattern.

You also have to realize it is not just the choke and ammo, it is also in part the length of the barrel you are shooting. For example lets take two guns that are the same except one has a 24 in barrel and the other has a 30in.both with icchoke. the shell fired from the shorter barrel is going to openup faster, giving you less range than the longer barrel. So if you went back and put a mod choke on the shorter barrel it would give you more range. maybe not more range than the 30 in with ic. but more than it (24 in) had with the ic. will very from: gun to gun, choke to choke, barrel to barrel.