9mm
Round nose bullets 5000 $500 $0.10 each
Brass (new) 5000 $880 $0.17
Brass (once-fired) 5000 $200 $0.04
Primers 5000 $140 $0.03
Total, excluding powder, about $0.30 using new brass(!) or about $0.17 with once-fired brass. However that’s misleading since the cost of brass is more-or-less a one-time hit. New brass is good for 7-10 reuses, knocking the total price down to about $0.15 a round.
Bargain shop a little bit more.
Brass is free for me (and many others). I go to a local public outdoor range and can pickup all I need and more.
Primers? I buy by the case when they're on sale. Last bit I bought was $240 for 12k (only a few months ago), which is $0.02 each. That was a local shop that I found those at, but I've frequently seen one brand or another on sale at $100 per 5k (Grafs has run Magtech on sale several times in the last few months at that price). Works out the same.
Bullets? Lately I've been shooting commercial hard-cast lead (if you're willing to cast your own this can be driven down even further, but I do draw my effort line there
). Z-Cast Bulletz 147gr 9mm is currently $25 per 500 - $0.05 each.
Powder? Lead takes less powder than jacketed - the heavy 9mm bullets even less. I use 3.5gr of Unique under those bullets above. Buying at the right times I can get Unique at around $18 per pound. 7000 grains per pound = 2000 rounds per pound = less than $0.01 per round, but we'll round to a whole penny.
So, free brass + $0.02 primer + $0.05 bullet + $0.01 powder = $0.08 per round. That's less than half the cost of factory ammo (which I probably could bargain shop for that too, but I haven't seen lately for less than $0.18 per round or so).
I'm sure components will go up some, but so will factory ammo, so the disparity will likely be maintained going forward. Realistically, there are almost no cartridges that "aren't worth reloading". Pretty much everything is cheaper to shoot when you reload - at least per round. A common truism is that people have a certain amount to spend and they'll spend that regardless of the cost of shooting. Ammo prices really just determine how far that budget will take you (ie, you'll spend the same amount, but shoot a lot more
).