slugs and buckshot work best. u should probably buy in 3" or 3 1/2 if u gun can handle it. i am also starting to hunt coyotes w/ a shotgun. sounds like a lot of fun. for buckshot u can shoot to about 50 yards or maybe even 65 if u have the right combination of chokes, shells, etc. but i wouldn't put on too tight of a choke or the pellets might deform. for slugs u can probably shoot out to 100 yards w/ the rihgt shells. but make sure u nkow where ur bullet is gonna hit if u dont have a scope.