Howdy,
My Winchester likes the Lyman #321197, a 185-grain FN GC sized .321" with 18 grains of 2400. Like most of my obsolete moulds, I found it on eBay. .321" stuff is hard to find, but there are bunches of moulds out there if you're patient. I also have the #319247, a 165-grain FN square base, but I like the heavier bullet for hunting.
Odd thing, though. With factory Winchester 170-grain ammo, it shoots just fine. When I started fooling with cast bullets I ran out of sight adjustment. A ladder-type carbine sight from Dixie Gun Works cured the problem.
Bitterroot Bob