Your 460 with 70gr of 777 will be going around 1150 to 1200 fps and will be more than enough to drop a whitetail at 100 yards. Here is a chart for that load at 1170fps.

Name: 50 Cal, NoExcuses SWC, 460 grn
Ballistic Coeff: 0.294
Bullet Weight: 460
Velocity: 1170
Target Distance: 100
Scope Height: 1.500
Temperature: 40
Altitude: 500
Ballistic Data
~~~~~~~~~~~~~~~
Range Elevation Velocity Energy ETA Drop Max Y 10mph Wind Deflect
0 yds -1.50 in 1170 fps 1398 fpe 0.000 sec 0.00 in -1.50 in 0.00 in
25 yds 1.48 in 1138 fps 1323 fpe 0.065 sec 0.81 in -0.39 in 0.15 in
50 yds 2.78 in 1109 fps 1256 fpe 0.132 sec 3.29 in 0.24 in 0.62 in
75 yds 2.32 in 1082 fps 1196 fpe 0.200 sec 7.54 in 1.35 in 1.39 in
100 yds 0.00 in 1059 fps 1145 fpe 0.270 sec 13.64 in 2.95 in 2.44 in
125 yds -4.24 in 1037 fps 1099 fpe 0.342 sec 21.67 in 5.08 in 3.74 in
150 yds -10.51 in 1017 fps 1057 fpe 0.415 sec 31.72 in 7.76 in 5.32 in
175 yds -18.89 in 999 fps 1020 fpe 0.489 sec 43.89 in 11.04 in 7.16 in
200 yds -29.32 in 982 fps 985 fpe 0.565 sec 58.10 in 14.90 in 9.12 in

Note it retains more than 1000 fot pounds of energy until around 190 yards and gives you about 120 yards of 6" point blank range. The fact that it shoots accurately is the most important thing followed closely by the energy that big bullet has. Good luck with it.