I patterned my 935 28" brl with a .675 ext carlson non ported choke with 3.5" #7 federal HW and got 216 in the 10" circle at a measured 40 yards.
The temp was 30 and the bore was DIRTY(never been cleaned). I used it the last part of duck season and during the snow goose conservation order.
Just taking a wild guess how much difference would a clean bore and warmer temps make? I am kinda hesitant to mess with it.
thanks
224tth
Clean it and you will get about 230 -250 as a guess.
Most guns shoot better patterns with a clean barrel, but you won't know until you try it.
Your patterns will almost certainly improve as the temps warm up. It's a good idea to pattern in cold weather just so you have an idea how your gun will perform in a "worst case scenario".
It sounds like you're already in good shape. I'd just clean it and hunt with it.