I did make the tommygun ever so slightly faster. This was my way of counteracting the weapon slow down bug; tested it as well and it worked fine. But it shouldn't be noticeable.
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The change is just 0.04 second, so it can't be that significant. I just checked killing speed of tommygun and minigun and the minigun still got it beat. Again, this slight change was one way to counteract the weapon slow down bug (the laser and flamethrower also have this kind of change). But if it's really a problem, then I'll think about adding a slight buff to the minigun.