i recently bought a mossberg 835 and wanted to mess around and do some clay shooting with it at the local range. i have 4 factory tubes which are xtra-full full and one says mod-T&F Steel-I.C.-all lead- and another that says mod 2 & bb Steel-All lead.im guessing that those last two are improved choke and modified? i will be shooting winchester super target 12 gauge 2 3/4" 1oz 8 lead shot.
If you are just starting out use the modified chokes and then progress to the fullest choke you can find. The targets will simply be blown to dust when you hit them with an X-full trap choke. Now you see 'm and now --- you don't!!
Of the ones that you have listed the IC will be your best overall choke tube. It will probably give you the best opportunity to break the variety of clays shown on most sporting clays courses around here. If you are shooting trap then I would go with the modified. Good luck!!
I second Mackgee
Improve dcylinder for everything out to 30yds and modified after that.
Most of the sporting clays courses only need improved cyl. for 90% and you can get away with them for the longer shots as well