I have taken squirrels and crows out at around 120-150 yards with .17 HMR
Deer hunting around here, the woods are so thick that shots are less than 100 yards, but closer to 50 yards is more common.
At these distances, barrel length really does not matter nearly as much as shot placement.
I hunt deer with a Marlin 336 in .35 Remington or .30-30, when deer season rolls around the only optic I plan on using is my Burris Fastfire III. In the 50-80 yard range, I can kill squirrels with it. Being able to hit a deer won't be a problem.