I started up the latest official version of FPSC (v112), set the player marker and assigned the weapons property to the bow and arrows from the fantasy pack. The default for ammo is "1". When I ran the test level it had the six reloads and that is what the hud had shown. I then changed the "ammo" property to 2. Apparently, this cannot be changed. You will only get the designated default value that is found in the gunspec.txt. In other words only one quiver of six (default) arrows. However, if you place the bow and arrow entity down in various places, each time you pick up the entity you will get an additional amount of arrows for your quiver. It will show up as an additional 6 (default) to whatever you already have. Also, I am not getting any error messages with the default.
I then changed the gunspec to 10 reloads (arrows). Retested the level and it did show 10 arrows in the hud and when I picked up another bow/arrow entity it added another 10 more arrows to my quiver. I did not get any error messages.
What version of FPSC are you using, CC10?
The past has a lot of memories to hold onto; but, today is chock full of new adventures, and, the future shouts out, "The best is yet to come!" -- TerryC