Surplus ammo...

[kilopaparomeo]

7.62 NATO brass -- $150 / 1000 / 5 reloads = $0.03 per load (I stocked up on several 1000 a few months ago)
147 gr M80 projectiles -- $80 / 1000 = $0.08 per load (I stocked up on several 1000 a few months ago)
CCI34 primers -- $0.03 per load
IMR 4895 -- $0.12 per load

Handcrafted 7.62 NATO = $0.26 per cartridge --- should be similar to your cartridges.  Doesn't take many rounds to pay off a modest set up.

Plus, I find reloading to be cathartic...