The Ruin Wings have the effect that heavy ammo drops more often. It does not guarantee drops, though. I'll show you why. This perk works with the ammo mechanism behind Destiny. Basically, this system works like this: [i]The less ammo you have, the higher the chance ammo drops (but it's not neccessarily 100%). [/i] The game keeps track of all your current ammo and reserves. If one of the ammos (for example primary) is depleted, you have a relatively high chance to get ammo for that type on the next kill. But there are a few variables: - the ammo in total (from [i]all[/i] types) - the type itself Means, that, as long as you have ammo in your speical and heavy, drops for primary ammo are not guaranteed. And the second variable is your problem: heavy ammo has the [i]lowest[/i] "drop chance" of all three types, since heavies are really powerful. Ruin Wings heightens the value of the "heavy ammo drop chance" variable, but still, as long as you have primary and special ammo this chance is pretty low, since you have enough other fire power to vaporize anything in your path. The only point where ammo drops for [b]all[/b] types are guaranteed is when you have no ammo at all. In all your weapons. I hope this little explanation helps!