I buy most of my stuff through wholesale sports. I use a 68 Hornady HPBT Match bullet, but they are the same price as 69 grain SMKs the Hornady's just have a bettter BC. I use 25 grains of Varget. My price is:
Bullets: $22/100
Primers: $42/1000
Powder: $32/pound
Brass: Free (I've never bought .223 brass, so much on the ground!)
Cost per shot: $0.22+$0.042+$0.114= $0.376
So 37.6 cents a shot x 20= $7.52 a box for match ammunition.
If I used a cheaper bullet, like bulk FMJ 55 grain I could get my bullet price down to 13 cents or so a round, which would make a box worth $5.72.