I shot a mule deer buck in 1985 with 125 gr jacketed bullet. I was 40-50 feet above it on a ridgetop, the bullet hit between the shoulder blades and it remains the most blood shot animal I have ever dressed.
I have taken several deer with a 185 gr rf bullet but they have been launched with a Rossi 92 at much faster than revolver speeds. Usually down within 20 feet. I would trust it over the 150's.

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Front sight and squeeze