I think 2a has a scoped magnum, making it easier to fire with, I saw on Space's server.
Magnum - 40 damage, 80 on headshot, 6 shots before reload
Scoped Magnum - 35 damage, 105 on headshot, 4 shots before reload
Currently the Magnum is more accurate when you're moving and firing at the same time, I can't decide whether it should be that or the other one due to the power of it.