chain speeds on my saws
To figure out chain speed you multiply the pitch of the chain by 2 and then multipy that by the number of teeth on the sprocket. now multipy by the rpm of the saw and then devide by 12. This will give you the chain speed in feet per minute.
My 075 has .404 pitch chain on an 8 pin rim sprocket and the saw runs at 9,000rpm. [.404x2x8x9,000]/12= 5,280 f/m
In contrast my 038M is running .375 pitch chain on a 7 pin rim sprocket and the saw runs at 13,500 rpm. [.375x2x7x13,500]/12= 5,906 f/m
those numbers would sugest that the 038M cuts slightly faster than the 075. What those numbers fail to show is that the 075 is almost 40cc larger and actually has the torque to maintain that rpm/ chain speed while the smaller saw cant even come close to running at its max rpm when milling.
I have no idea what the amximum chain speed would be for milling or if it would come down to swarf clearance for the tooth design or maximum power/ load on the chain. someone up at Madsons may be able to help you with the info as well as some of the parts for the chain drive on your mill.