I might have added that you generally match powder and shot by volume, so use the powder measure.
70 gr powder = 1 oz shot
90 gr powder = 1 and 1/4 oz shot
110 gr powder = 1 and 1/2 oz shot
Not to overload you with information but the following links are excellent reads on ML shotguns, the last link is working up a turkey loads.
http://members.aye.net/~bspen/shotgun.html
http://members.aye.net/~bspen/starr.html
http://www.98.net/ibha/shotguns.htm
http://members.aye.net/~bspen/SmoothboreLoads.html
http://www.caywoodguns.com/working_u...s_for_opti.htm