I didn't test all types, but e.g. seeker shots cannot be crafted into a magazine. Surrounding an empty magazine with bullets gives me back an empty magazine.

What version have you tested this with?
Is it in a modpack?

I have tried testing this in dev, that is with the same code as 1.12.2-1.3.4.719 and I can see the recipes working correctly.

I made a fresh instance and tested with just reliquary; and you are right, it works there so it must be a mod conflict. I'll see if I can find which one. I'll close this for now.