If you're the squeamish type, get a pig and kill it with a knife. It'll get you used to the blood and screaming/squealing.
Anyway, good luck hitting man sized targets out to a 1000 yards with any sort of off the rack hunting rifle. That sort of thing isn't all that common even with a precision rifle, expensive optics, match grade ammo, a spotter, and the training how to use it. A good part of such training is actually how to lay still in your own waste while terrible insects bite you. Not much fun.
I couldn't get ammunition reliably during the recent ammo panic. Even the really odd stuff got snapped up, like 70 plus year old stocks of 7.35mm Carcano.
Good luck capturing weapons too. That presumes that you hold the ground at the end of something and that whoever you're trying to recover things from didn't have friends.
Anyway, I live on a Marine base. There are three recruit battalions, the weapons bn, and what not.
What could happen, and I'm actually surprised hasn't, is for three or four shooters to pull a mumbai and get into family housing and attempt to run up a score. (Crash the gate, sneak in via delivery truck, or just get in via the swamp.)
I've got two M4 clones and a Colt 6500 - basically a transitional A1/A2 hybrid. I've also got an M1 carbine a Mini 14 and a bunch of other things.
My current M4 clones are a straight CMMG and a CMMG lower with all Colt parts. One is back to iron sights, the other has an older Aimpoint Comp M on it. Either, or the 6500 will work fine. Since the operative word was "rifle" and not "carbine", I suppose the answer is the 6500.
My wife is a Corpsman, the AR platform simply makes sense. When the boys are older, they can have the extras.
I keep 75 odd AR mags laying around loaded. I also have 1000rds "rainy day" can of GI green tip on strippers handy. I keep 6 mags in my Eagle chest rig, along with my G34 and a total of five mags for that. That goes on over my Izzy tac armor with level IV plates (allegedly multi hit) front and back. A rifle is only part of the answer, your accessories are what can make the difference. (My wife has her own armor and a reasonaby stocked medic bag.)
Though I have a PVS-14, I've yet to get an IR laser/illuminator mounted. Eh, other priorities. I suppose I should get one of the M4's a can too.
Truth be told, I plan to get a SCAR-H when those become commercially to be had in a bug free format and if the new Leupold HAMR works out, just mount one of those and be done with it.
Those interested in this sort of thing will find it more useful to have a suppressed weapon with IR target aquisition systems paired with American made (ITT) NVG than to worry all that much about caliber and platform. Just tuck the gun under your arm and follow the dot that only you can see at night. Tape down buttons on your remote controls and you've got makeshift IR IFF units. The can isn't so much to kill the noise as to eliminate the flash.