I agree that 100 grains isn't required. I just ordered some lighter bullets. Most of the lighter bullets, however, are geared towards varminting and either blowing up on impact, or not destroying the pelt, or both. I did find some geared more for more controlled expansion and penetration.
I used to hunt on a plantation where I had free roam over the place during weekends and evenings (no morning hunts), but I could not shoot a deer unless it was a 100% sure kill. They gave guided horse-drawn wagon quail hunts to the wealthy folks, movie stars, football coaches, and the like. They did not want to stumble across a gut shot bloated deer with vultures pecking at it on their hunts. I quickly learned to be very accurate and I learned to make head-shots. The guy that ran the place showed me that you can look through the scope, get it near where the head will be, and whistle loudly. Every time, the deer would lift his head and look right at you. Then you quickly adjust your aim and shoot. Either you have an instant kill or nothing at all. (well, sometimes he wouldn't even run, he'd just go back to grazing and give you a second chance, but I rarely missed). I haven't hunted there in years since new management took over the place, but I am still hung up on having that uber-accuracy and instant kill. No suffering for the animal, no tracking to be done, and no meat wasted. A varmint bullet would more than suffice for that I suppose, bit I still want some heft.