The GAU-8 is fast and deadly. The thing that is REALLY good about it is that is has 999 bullets! I suggest saving up for the Jackhammer then from there on save up for the GAU. The thing about the GAU is it's perfect for spraying, but it is best to use 1 bullet at a time, when facing small mobs, one normal zombie will die from one GAU bullet. Have fun!
Pancor Jackhammer - My personal favorite, FAST reloads, good spread, not that great range, but the power makes of for it, i suggest starting out with it at the beggining if your facing mobs.
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