Error message: https://imgur.com/a/GrHEZKi
First apply the fix by yavis1231 to load a save file with the mod enabled in 1.1.107: https://mods.factorio.com/mod/ammo-loader/discussion/6618147d07a77216cd2d8131
Then place a furnace, gun turret, or artillery turret to trigger the new crash. Vehicles such as trains don't seem to cause this crash in my save.

Your problem should be caused by a conflict with another mod.
I used to have a similar problem with an older version of Logistic Artillery, because it added a lot of variety to the shells.
So you should troubleshoot your list of mods, especially the ones that add a lot of ammo types.

Hello! Thank you for using my mod!

This issue is caused when the per-map mod setting "Loaded item stack size" is set above 255. I just released version 1.1.40 which hard caps this setting at 255, which should solve the issue.

Let me know if you have any more problems!

Thanks, it works for everything now :)