(seriously, the difficult thing about 'spares' is they eventually turn into 'spare rifles')
That's a great configuration for your spare parts. AR for everyone in the house, plus one.
"one"? (grin)
(i'm around plus 10 or so after outfitting both of us.....if you count the ferrets i'm still plus 4 or 5; i've kinda lost count on the rifle front)
AF,
I was paraphrasing the "minimum" standards....I left off the 1k round per rifle minimum as well.
If you have more, so much the better.