I believe it was for PVP purposes and the fact that sometimes even after several minutes has passed since the heavy drop, some people are still running around with machine gun ammo effectively using it as a primary.
The counter to this argument is that in the D2 beta, the fusion rifle gets six shots after picking up power ammo effectively making it the new "machine gun" of D2 so to speak.
Thoughts?
[i]~Nyahh! =^,.,^=[/i]
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As soon as it was said I knew it like 99.999% of the changes was in the name of PVP balance. Since power ammo spawns regularly if something even close to Tunderlord was in the game well that would be game over man game over....Thunderlord you will be missed. Every time I loaded that bad boy in pvp I would hear AC/DC warming up in the back of my head....