What really stinks is when you've got your finger there holding it. Done that, went almost through my thumb, and that was with a #8 nail.
I did have the same thing this weekend, took the nailer apart twice before I realized it wasn't the nailer but that I'd unplugged the compresser to plug in the saw and forgot it. DUH!! (my excuse is that I haven't done this for a while and was in a hurry to get it done and distracted!!)
I had a picture of me holding a frame with a staple comming out right thrugh my fingernail on my old phone., dont take but once like that and you never hold close while shooting again.
I was having trouble getting the staples to recess one nite, like they always do when the compressor is about to kick on, so I thought enough of this I gonna reset the preassure switch. Cranked it up and tried to staple, still wouldn't recess the staples. Went and turned it up again, again no joy! turned it up all the way and still wasn't working.
tore the stapler apart, checked and cleaned all the parts. still didn't work. After midnight by now so gave up and went to the house fuming. Next AM walked to the shop with coffee to further study.... was sittiing there pondedring the problem considering going to buy a new gun, when my eyes swept across a shelf with various cans of paint, rubbing coumpound and ...... a lone bottle of..... "air tool oil" ........ 4 drops in the air hose connection... been working like a top every since.
Aint no fixing stupid.