Sounds reasonable.
I try for 2" at 25 yards but the target on the first page of this thread (I thought was pretty darn good!) has 10 in about 2 3/8" although 8 are in a 2" circle. (Truck hood rest, 6" barrel the 4" Combat Masterpiece should do as well I think).
4" at 50' is something to shoot for but more than 5 without a flyer would be might good, IMO. No question the thumbrest grips help offhand shooting. Are you going to get some for the Combat Magnum?
Personally, I don't care where the group is on the target if I've got adjustable sights as one day I just might adjust them.
It's those darn flyers that are hard to account for!!!
