Welcome to the forums, madmax
Generally weapons names for addons will be listed in the readme (if they're not then the author has missed finishing off the addon properly).
Failing that, you can get
any weapon or magazine name by placing a trigger in the mission editor with the following properties:
TriggerRadius: 0,0
Condition: radio Alpha (repeatedly)
Condition Field: this
OnActivation: hint format ["%1\n\n%2", weapons
unit , magazines
unit ]
By pressing radio alpha (0-0-1), that will give you a list of the editor names of all the weapons that
unit has in their posession. The line below that will list all the editor names of the magazines that
unit has
This works on vehicles as well as men...