When I reload for my 1911/.45 ACP, I use my own cast bullets. The cost is primers and powder. I have a lot of primers on hand. Let's say that they cost me $0.02 each. Powder at 5 grains a charge is 1400 loads to a pound. At $20 a pound - for powder on hand - that is about a penny and a half a charge. So... one round of .45 ACP costs me about 3.5 cents or $1.75 a box.
If I use jacketed bullets, the cost jumps up about ten cents more per round or about $6.75 /50.
Loading .223 ammo, using Sierra 77s, is about 25 cents a round or $5 a box of twenty.
Pete