Southern Shooter,
I would suggest that you spend money on ammo for now. However much you can carry is all you will have when you bug out. Ammo bought now means you can practice, now and maitain your shooting abilities in the future. FIgure out how much you can or will carry in a bug out situation and always have twice that on hand as a minimum.
Think about, if you are bugging out on foot, which is likely to be more useful a fifth loaded 30 round magazine or a decent water purification system and a couple or four energy bars?
If you have a place you are bugging out to, have more ammo already there and if you do use your mini have a few spare magazines there in case you loose one or three on the long march.
Don't know if .223 is legal in La. but here in FLorida more than a few deer are taken with .223, mostly the 52-55 grain soft points. An aquantence that had proper permiting took nusience dear in a citrus grove using 55 grain M193 hardball and used the heart lung shot and said the four he took never went more than 30 yards and only one at that.
I once had a Grand Uncle by marraige that hunted and took deer and turkey with a .22LR. His son grew up to be come a Game and Fresh water fish officer BTW. Ranges were close and likely over baited feilds as well. He also fished for ducks (and no I will not discuss that but to say animal rights folks would truely freak) and trapped Quail.
As the song goes, a county boy will survive, especially if that country boy needed to feed a family during the depression as Grand Uncle did.
If your Mini was to be the only rifle you have you might consider a Ciener .22LR conversion unit for it. Cheap practice after a few hundered rounds and the option of haivn a .22 rifle and .223 rifle all in one. Barring that you may want to see about getting a "shell shrinker" single shot adaptor with a spare firing pin assembly or two and carrying your Bug Out Mini with a .22LR up the snout for rabbits, squirrels, raccoons, posums, stray dogs or whatever of opertunity. I do not know what sort of accuracy you could expect from your rifle or how yours will handle target (sub sonic) ammo or CBLongs but it will give you an option of a much quieter single shot than firing off a .223. If you suddenly find yourself confronted by raiders or zombies or aliens or Jack booted thugs of the occupying army cycling the action will eject the shell shrinker and load a "real" round of ammo.
Again if you are actually going some place, have .22LR ammo there and a dedicated more accurate .22 Rifle there.
More important than what rifle to take is where are you going and what will you do there.
Roaming around in the woods just ain't going to get it. There are going to be a lot of hungry folks doing the same and a lot of folks that have a place and don't want you in "their" woods. Get friendly with those forth cousins you never see and figure out how you can be of use to them if you show up hungry and armed at their farm. Remember great Aunt Sookie over in Smallville with her little frame house and garden plot, now is a good time for you to get frendly and helpful with Aunt Sookie and maybe hint that if there was trouble in the big city you might come out to live with her just to help her along in her old age (and really do help her now.) Sure your old Service buddy, high school/college buddy, job buddy, former cell mate(I hope not if you are on here) once got drunk and siad "I love you, man!" but does he really love you enough to let you and your hungry kids move in and take food from his kids mouths? FInd out ahead of time and make plans ahead of time. Like help him close in that garage for a game room that later you might be able to live in and help him drive that sand point to get a well with usable water even though is is currently on city water, invest in that old friend ship and make sure that if he is the one that needs to bug out that you can put up his family and feed them a bit.
Rich? Got a vacation home you are headed toward? who will be living there when you arrive and how exactly do you intend to get them out? How about getting someone already close to the site to move in when the SHTF and hold down the fort? Sure you may end up sharing with them and not having all you originally planned on but beats wandering about in the woods all to pieces. You are going to need someone you trust, some one you invested in for that as well.
Lot more to think about than which rifle.
Get good with whatever you have and stay good with it and have the accessories and ammo you need and will carry with that gun.
Have fun and be safe,
-Bob Hollingsworth