Since you mentioned in your initial post that you plan to bug out via vehicle, and that you have a variety of other scoped hunting rifles and a shotgun.....
I would suggest that you keep both and sell some of those others off if you have to tone down the herd. Keep a decent rifle chambered in 22lr however.
If you must pick between one or the other, then sell the Mini14 and keep the M1A. Spare parts are easy to obtain compared to the Mini. Since you own both, it is obvious as to which iron sighted rifle has the better sights.
The only reason that I would consider ANY rifle chambered for 5.56mm/223 as an advantage over a rifle chambered in 7.62mm/308 in this case, is if your space available in your vehicle is limited in terms of hauling ammo. More 223 can be had in a given space compared to 308. ( I dont buy into the finding of ammo post SHTF either..... and just as likely to find a rifle with a half loaded AR mag sticking out of it regardless...lol)
Then again, shotgun shells fill up more space than either, so the shotgun could be sold off, if space for hauling ammo is limited.
FWIW..... I would choose a well built M1A/M14 over a well built AR regardless, and have not missed my Colt one bit. Same for 2 Mini14's, 1 Galil, Rem model 7, 112 Savage, HK93, and an AK chambered in 5.56mm. ( I sold off all 5.56mm rifles after being involved in operations in Iraq and Afghanistan). All SKS/AK rifles were liquidated, along with various bolt action rifles in a multitude of calibers. M1 Garands were also sold off, as well as my HK91 and FAL. Also put all but one shotgun on the chopping block. I still have all my rifles chambered in 22lr however, along with most handguns.Decided to keep the M1 Carbines. (Wife and kids love um)
Besides...... if you like the ergonomics/manual of arms of your Mini and Socom, and shoot them well, then switching to something else isn't all that great of an idea anyways.
7.62x51mm/308 is the more versatile caliber between the 2 being discussed here IMO, and from my experience with both. Effective range, and penetration are more important to me vs lightweight, and especially if the plan calls for bugging out via vehicle.
FYI....... A 20rd M14 magazine topped off with WIN Q3130 = 1.5 lbs.
SAI states that the Socom weighs in at 8.8lbs, but I have 18in barrel versions that weigh in at less than that.
You could always consider a bigger vehicle
11B