[Jimbuna]

I agree with KL.

Take a look at your mods when you open JSGME, if the Additional Ammoe mod (not a GWX mod, but a third party mod btw) is greyed out, that tells you it has been overwritten by some other mod.

Remove the mods one by one and as soon as the ammo mod regains its black text, you will know which mod is overwriting it.

If I was a gambler, my money would probably be on the deck gun range mod because the all weather guns mod (which is also a third party mod) is definitely compatable with the ammo mod.