I'm on the road so have limited ballistic information but here is a basic comparison:
Muzzle FPS/FtLB @100 yd @200
7x57, 139 gr 2740/2317 2555/2015 2318/1504
45 70 , 325 gr 2050/3032 1729/2158 1450/1516
The bigger difference is in drop; @ 200 yds the drop on the 45 70 is more than 4" greater than the 7x57.
I would not consider the 45 70 to be much more than a 100 yd gun.
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