When I first started a few months ago I purchased a southord pick set and a LockAid pick gun.
I had absolutely no luck with the gun. I tried everything mentioned here and could not open one lock with it.
After I became comfortable SPP and understanding the inside of a lock better I gave the gun another try.
Opened a fairly easy lock in two clicks. I have been able to repeat this with no more than five or six clicks at the most.
So any of you new guys that are having problems and you haven't really tried SPP, give it a try and really get to know a lock and give it another try. FYI, I had mine set at maybe a half turn from the lowest setting.
To tell you the truth I really don't have much interest in the gun since I learned how to SPP.
It's way more fun.