Just got my second US-50. You rush all the way up to half or 3/4 field on xball and you shoot them in the snake that's what I do with it. Up close having a small gun can make all the difference when you are leaning around a corner.
Here is a clip of me playing with my axe and you can see me shooting the US-50. It wasn't loaded all the way so I could show you it can hold more than 22 but it definitely can.
I had to clean all the paint off of the moving barrel and spring there it was gumming up the whole gun.
The valve assembly (orange and metal) that pierces the 12 gram which the hammer hits has a flathead screw on the front side of it I wonder if that would adjust the velocity? How far would you turn it and which way to turn it up? I am afraid to mess it up what the setting is.