Here there Jim shoot the 150 TSX with absolute confidence. It will pass thru mature elk even on sharp angled shots from front or back. . Because of it's length it will carry well. I have my own range out to 522yd & have seen many of the Barnes TSX bullet which are considered light for cal do quite well. These bullets are long for their weight . Some shooters only look at weight & fail to understand the BC of theses bullets. . Don't be afraid to use the 150 in your 300. It's performance ability will amaze you once you actually shoot some. Save the heavier 168's & 180's for King Kong.