You will have to experiment to find out.
Yes, but check your pattern. Most shotguns will pattern buckshot best with a more open choke.
modified or cylinder - get both and try them out
From Mossberg's website:"Can I shoot slugs or buckshot through a "smoothbore" field barrel with Accu-Choke™ tubes? (500/505/535/9200/88/930 models) Yes, and with sabots or rifled slugs, the more "open" the choke tube, the better the accuracy ("Improved Cylinder" recommended.) The "full" or "modified" choke tubes are preferred for buckshot loads. Slugs, buckshot and steel shot loads are not recommended for use with an extra full "turkey tube" installed, due to the tube's tight constriction. Do not fire any load without a choke tube installed, doing so will damage the internal choke tube threads. "
DO NOT ATTEMPT TO FIRE BUCKSHOT OUT OF A THREADED BARREL WITHOUT A CHOKE TUBE INSTALLED!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! Danger, Danger, Danger
Yes. It should pattern well and the effective range should be increased slightly.
You will have to experiment with different loads from different makers and different chokes. Doubtbul that one choke will be the best at all three ranges.
This is a job best left to a trained gunsmith.
A full choke is the best for waterfowl.It will keep your pattern tight as long as possible due to the distance involved with shooting ducks and geese in flight.
Same choke tube as a 1200 or 1400 pump
wiring diagram of electronic choke in tube light
Improved-cylinder, or skeet barrel. "Modified or full-choke barrels (in any make gun) simply will not shoot slugs or buckshot as well as the more open chokes." --Edward A. Matunas; "Deer Hunter's Guide to Guns, Ammo and Equipment", 1983