Not a .257, but a .240 Wby, 80 gr. TTSX at 3,600 fps. Slightly smaller version of the above. Chest shot a doe at a hundred yds. or so. She ran over a hundred yards, had to find her in the woods at night with flashlights.

LOTS of superficial damage to rib cage, small entrance and exit wounds in chest. Not enough internal damage to suit me.

Not too unlike the .257 Wby scenario, seems most of the K.E. was expended BEFORE the bullet entered the chest. I think these fast monos do best busting bones, shoulder shots, head shots on hogs, etc. Maybe 3,600, 3,800 fps has reached the realm of diminishing returns. Terminal ballistics is an interesting study. Matching bullets and velocity for optimal performance on game animals is an art more than a science. IMO...

Now, my .257R, shooting 100 TTSX's at 3,250 fps, seems to do better on WT chest shots, is my go to bullet in that gun. BTW, sub MOA accuracy over max H100V loads.

My current go to bullet with the .240 is a 100 gr. NPT. Not as fast, but terminal performance on chest shot WT's and Pronghorns is much better, usually knocks their nose in the dirt. And, in that gun the NPT shoots half MOA or better, shot one group of 1.7" at 400 yds. Can't say I can do it again, but the gun did it once...

DF

Note entrance wound and chest exit wound.

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