25 steel to turn 100 piercing rounds into 1 box equal to 100 piercing rounds? That's an increased cost of 25% for nothing but inventory space. I consequently didn't build the ammo boxes in my last game, but I'm assuming that ammo boxes can't be divided, so you can't give small amounts of ammo to turrets.
Wouldn't 1 steel make more sense? You're not getting more ammo, you're just saving inventory space, and steel is pretty valuable. Not to mention... it's a box, not some complicated device. Production should be cheap and easy.
Balance-wise, I feel like this mod is trying to play conservatively and have low impact by not being too easy to get. I think this effort is massively overdone. It's just inventory conservation, right?
Am I missing something about what the ammo box does?

Donno if its been updated sense the you posted this but, each box is 1000 rounds, so 100 boxes is around 500,000,000 rounds, in the end, you spend about 500 steel to nearly triple the amount of rounds you have.