Cool!
In very older days I used 47 grains of surplus 4831 with any ol' cup and core 100 grain bullet. Deer die.
More recently I've used the 120 grain partition, federal magnum primers, and 43 grains of H414. The last deer I shot with it was more or less head on. I shot it right under the chin, broke it's neck, the bullet exited out the back of the neck, went through a few inches of air, went back into the shoulder, and went right down the rib cage tumbling but cut every rib off. Total penetration was about 20 inches of bone and meat plus 3 layers of hide.
Of the .257s I've shot, there has been either a really clear like or really clear dislike for 100 grain bullets. If 100s work, awsome. If not, try 120.
Don't overlook the hornady 117 grain BTSP, 110 grain accubond, and 115 grain ballistic tip.
