I shot some Greek ball, Winchester Silvertip, and my handloads through a No 4 rifle. You can look at the velocities. I think IMR 4064 is an excellent powder in this cartridge and you can use 180 grain bullets and they will shoot close to what the 174's will print.
Code:
No. 4 MkII
180 gr R-P (.310) RN 42 grs IMR 4064 Lee Scoop 3.1 Hansen cases Fed 210M
30-Jul-91 T ≈ 90 °F
Ave Vel = 2470
Std Dev = 61
ES = 193
Low = 2430
High = 2623
N = 10
174 Greek Ball HXP 70
9-May-92 T ≈ 70 °F
Ave Vel = 2488
Std Dev = 12
ES = 27
Low = 2473
High = 2500
N = 5
174 grain Greek Ball HXP 70
8 Feb 2012 T = 50 °F
Ave Vel = 2423
Std Dev = 14
ES = 53
High = 2456
Low = 2403
N = 14
180 grain Winchester Silvertip Factory Ammunition
8 Feb 2012 T = 50 °F
Ave Vel = 2297
Std Dev = 14
ES = 46
High = 2319
Low = 2273
N = 10