For a SHTF type of scenario, I think the Mini-14 would be a decent choice.
While it is not as accurate as an AR, it does have decent accuracy (the newer ones will do 2 MOA, 2” at 100 yards, with the right ammo) and can be made more accurate for relatively low cost ($100.00 – 150.00). It is reliable and handles well. It is chambered for .223, but is designed to handle the 5.56mm so ammo availability should not be an issue, the Military uses 5.56mm and most law Enforcement agencies use either .223 or 5.56mm.
In my mind, it only has a few drawbacks:
1. The magazines are more expensive than those for an AR, however, the difference in cost for an AR will cover the Mini magazines.
2. The magazines are not as easy to insert into the rifle as those for an AR. You need to insert them at an angle and then rotate them rearward to lock in, like the M-14 or the AK. Not difficult, just not as easy or quich as changing the magazine on an AR.
3. The Mini does not come with any rails so adding attachments is not as easy, you will need to add the rails before adding any rail mounted attachments.
I also think it has some strong points in its favor:
1. Since it does not have a pistol grip, it is generally looked at as being more “politically correct”.
2. It is less expensive to purchase than an AR (base Mini vs. base AR).
3. It is very forgiving of poor maintenance.
As for the .223/5.56mm round… Yes, it is quite capable in a self defense situation. 7.62 or .308 are also very good rounds but are heavier which means that you can not carry as much ammo. If you also have to worry about food, the .223/5.56 rounds can be used on just about anything from rabbit to white tail deer. The 7.62/.308 will not be of much use on anything the size of rabbit because there just would not be much meat left; it would be usable on larger game that would be too big for the .223/5.56 round.
FMJ vs. JHP… I would go with either JHP or soft point ammo in either .223/5.56 or 7.62/.308. The only reason that I would go with FMJ would be if I was legally required to, like the Military is. Either JHP or soft point will work for SD as well as hunting so you do not have to worry about which ammo to carry.
Would I choose the Mini-14 in a SHTF scenario? In a heart beat!