I reload shotshells.
You can maybe get it down to around $3.00 a box for a box of 12 gauge shells, and less than that if your buddy gives a coffee can of shot he found in his Grandfather's basement
.
That's about half to a quarter the price of a factory loaded box.
But, like other posters have mentioned, you also gain flexibility in being able to customize your ammo.
I can make low recoil loads for when I want to shoot Grandpa's 6 pound single shot, experiment with PC Post wads and other things to open up patterns, and do all sorts of cool things.
It's worth it.