I'm not sure how this is possible unless you are using stockpiled supplies from 20 years ago. I can buy Winchester 555 ammo for around $22 per box at Walmart, for a cost of just under $0.04/round. Last I checked, primers cost almost that much on their own and then you need to buy powder and find a bullet supply. Unless you have free lead, even casting your own will cost something. I'm not saying reloading and casting aren't a great idea and you can certainly cut ammo costs down, but there is no realistic way to load .45 for even twice the cost of typical bulk rimfire.
I like the bigger holes, too and wasn't really serious about shooting rimfire only, but the costs certainly are good with the .22's.
Mark
Well the last time I picked up a brick of CCI's they were $29 +tax for 500 which comes to $65 with tax for 1000, I guess I'm getting hosed. I know I can buy garbage Winchester rimfire ammo, but I won't.
Primers I pay no more than 4 cents each as you say but I often get them for much less. I just bought 2000 Winchester large for $40 cash at my range (2 cents each), lots of deals out there but we will focus on retail prices here.
Brass I've collected from factory ammo, range scrounging, non reloading friend donations, etc....never once paid money for 45 brass.
For powder I use titegroup, I paid $25/pound when I bought 8 lbs. = $28.25/lb(7000 grains) after tax = $0.00403/grain
I do cast my own projectiles from WWs donated from several mechanic friends, and lead flashing from roofing. I have never had to pay for lead yet and won't have to for many years to come. I also happen to be a printer and I'm sitting on a sh!t ton of Lynotype as well, all free from work.
Now the math.
Brass = $0
Powder charge is 4.7 grains = $0.016/round
Primers $40+tax = $45.20/1000 or $0.0452 each
Projectiles are free except for my time and a little propane.
So that works out to $0.0612/round or $61.2/1000 using inflated prices and not including the cost of propane or hydro for my Lee pot. $12 in propane will smelt hundreds of pounds of lead ingots for casting, the cost per round is so low it cannot be factored in.
So yes it is possible and as I said earlier, it costs
me $65 to load 1000 rounds of 45ACP about the same price
I pay for manufactured 22 rimfire.