Actually that one looks just fine. But the hand is too small thats the only difference. Make the hand normal size in that configuration and it'll be good to go.
Except... I think you May have scaled the gun itself Too Small. I dont know for sure but it seems rather small.
And to avoid double posting...
I grabbed a perspective view of the plasma rifle that somebody threw together recently. I actually loved the way it looked but it needed alot of cleaning up. I added some personal touches also. Its not finished, and I may not take it further, but others (including OP obviously) are fine to do stuff to it. The added lights from the rear thing that sticks up (a wireless hud camera sight?) were a great touch, and I think they could be animated for idle frames.
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