223 is legal for Deer in NB and Maine for sure, any centerfire is. .22-250 is fairly popular for it here at home. Rocket Surgery is right, with the right loads, you can get by. its not ideal, and shot placement is a bit more critical, but it can be done.
.........it's not ideal, but it can be done. Yea,.....just like running the Daytona 500 in a stock Chevette. Those words always make me feel warm and fuzzy inside, when I have an oppurtunity to plan in advance to give myself the edge, oh and yes I read "The Most Dangerous Game", but will not limit myself to the Professional Hunters choice of firearm used in his island hunting perversions.
To the OP,.... you planning on deer hunting, get a deer class rifle. The .308 Winchester you can use as your benchmark. Adjust up or down carefully noting your benchmarks energy at 300yds, call this minimum for reliable penetration to the vitals of any deer and with enough oomph to cause rapid incapacitation.
Look at other calibers up and down the food chain from your bench mark choice(.308Win@300yds), noting this energy level at the range you will never shoot beyond and presto, you have your minimum.
Just for somewhere for you to start, you say you are new, launch Winchesters online ballistics calculator.
Select a .308 with 150gr Xp3 from the drop down menu
Select a .223Rem with 64gr PP from the menu.
Press shoot, and compare ballistic stats.
You will note the ,308 has 1649 ft-lbs of energy remaining at 300yds. This is your minimum.
You will note the .223 has 1249ft-lbs at the muzzle.
So unless you can get the deer closer than the muzzle touching his hide, it falls off your list.
So when you are more experienced with your scaphel, then you can start performing the feats of a surgeon. Until then, use a bigger stick.
Good luck with your choice, and shoot often.
