I have yet to try a 158gr for deer but I have loaded the Speer #4223 160gr JSP in my old M19 with a 6 inch barrel with a maximum load of Unique powder that gives me..........
1233 fps and 538 ft/lbs of energy that has taken BIG Nevada Mule deer inside of 100 yards. The last one at 60 yards hit
center line behind the shoulder at a perfect right angle, dropped in its tracks.

I have only loaded the 140grs for target use and the maximum velosity so far is just 1250 +/- fps that has 485 ft/lbs of energy but I do have a load that will come close to 1324fps but have yet to chrony it.

You can load heavier bullets but I do not think they are needed on deed size animals, if you can place your 1st shot into the vitals. No way would I try a bullet less than 140grs due to lack of penetration if bone is struck.