Though it's not a direct comparison I have clocked the 200SW out of my 26" 50cal using 100gr of FF 777 and its muzzle velocity averaged 1988fps. The FFF velocity may be slightly more, say around 2050fps. I have found the difference in velocity of 3F 777 vs 2F 777 to be small, usually under 100fps. I would think the 45cal will produce a bit higher velocity than the 50 but your barrel is shorter so if you were to use 2000fps for your calculations youshould be close enough out to around 200 yards, of course your going to verify the results at the range aren't you? Of course you are, any reason is good enough for another range session.
