medicboy: I can't tell if this is a trool or a legit question so here are a few observations. ???
An M1A is a poor choice for a do everything rifle, you might get my with one of the new M14's (note:not the mini 14 mut the updated version of the M1A) but I think it is still a poor choice. There is no real good compromise between a hunting and battle rifle. Your best bet is to get a nice bolt action for hunting. I couldn't care less for hunting but in case I ever do, I can have a bolt rifle, sure.
What I am talking about is a
paramilitary/survival rifle that would be good for combat, for medium-range 4-600 yards sniping and could also be used for hunting in emergency. The rifle one would grab if it was the only one he could take with him.
Hunting pretty much means .308, not .223. .223 does not fragment beyong 200 yards, so it will not drop a dog, let alone a deer. With people it may be fine as a wounded enemy is still out of action but a deer that did not die in place is a wasted shot.
M1A was successfully used as a battle rifle and as a decent sniper rifle. No AR-15/AR-10 would ever compare in reliability. M14 is the same as M1A except full auto, which I do not care about, and illegal to own.
The M1A comes in 18" and standard 22" barrels. I was just curious what I lose in exchganges for weight/mobility.
ditching the pos mini14, buying an ar-15 style rifle and going from there. Not allowed to own in NYS. No AR-15s/-10s, no AKs, no SKS, no Highpoints, nothing with a pistol grip, no FN/FAL. Nothing but Mini with 5-rd magasines. Have to keep it (and 10/22) in my Brooklyn home.
Barrel weight only comes into play after several shots, they resist heating up which could change point of impact. Barrel weight is what determines the stiffness and thus the magnitude/consistency of harmonics. Also inertial stability. The heavier the barrel, the better. Even 10/22 target shooters use .92 barrel to shoot .22lr at 100 yards.
mrblack: And I have to agree with medicboy miko You will indeed loose 50-100 Fps per inche of barrell length.
The Garande Is a little complexe for an all around weapon. Right. But 50 or 100 are two different things when we talking about 4 inches. It's one thing to lose 200fps and another one to lose 400 fps from what, 2750fps?
The Garande Is a little complexe for an all around weapon. 
Garande!? M1A - civilian version of M14, not M1 Garand.
Didn't I say you should be more attentive...

Anyway, what I am considering is basically what you had or maybe even an upgraded version.
miko