There seem to be at least a few inconsistencies between the Bungie API values for weapon mag sizes and in-game values. Not sure what'd cause this but figured I'd point it out. Blast Furnace, Last Perdition, Bygones, and Outbreak all appear both in the companion app and Light.gg as having exactly 2 less in the mag than they actually do. I'm not sure where else to post this or who to, so I'm hoping that someone who has a better idea than I stumbles upon it.