Just gotta go on record seconding the opinion: Use what shoots best in your rifle.

If you go with factory loads, like me, pick among the brands that are readily available - even on Friday night when you realize you need a box for Saturday morning. Therefore, I experimented a little with the absolutely most common brands around here and tried 150, 165 and 180 grain. All will be very effective with deer. I settled on Remington 180 grain corelokt PSP - because (1) they shot as good or better than any other common options (in MY gun - maybe not YOURS!) ... and (2) available in almost every store that sells ammo around here, from my favorite gun shop to the "open til 10" big box stores. If the Federal or Winchester factory loads, or another Remington weight, worked as well, I would have chosen it. I'd prefer to try a blunt nosed Remington corelokt, or similar, but it seems the PSP are the only ones commonly sold around here. I really feel the differnce (to the deer) is non existent and accuracy and confidence is everything. Even if I travel out of state and need to buy a box of shells locally, I know the 180 gr. Corelokt PSP's will give me within 1 - 1.5 inches at 100 yds, from box to box.

I go a different route - different slug - for large game such as moose.

I'm not a real "bullet head" meaning I like to shoot and experiment, but I'm not the most dedicated guy. But it was really amazing to me how much difference in accuracy there could be between same weight bullets by different manufactureres, and different weight bullets of the same manufacturer. For instance 150 remington corelokts were around 3 inch groups out of my gun while the 180s were over an inch, but consistently less than 1.5. There were a few that were in what I consider hunting acceptable for me - 2 inches at 100 yds., but the Remington 180s just seemed a little more accurate, consistently. It's also surprising how two different, say 180s, both firing within 2 inches would give significantly different impact points - side to side or vertically. Just fun looking at this stuff.