My cats are good outdoor mousers but most of the time they bring the trophies in and drop them, usually alive.
The little vermin get behind desks, under computer cords, in corners where the house was added onto...
I went and bought a Daisy pellet gun. The cats stand back like safari gun-bearers. I'm like a kid again.
I talked to a competitive shooter that said he took 22 short rounds and cut the bullet off at the end of the brass. He said if he missed a mouse he sometimes left a little dent in the baseboard.