I'm thinking about getting one of these for shooting groundhogs around my house in directions that I really don't think it's safe to shoot a firearm because of possible ricochet issues. Yea, I know this can still ricochet but nowhere near as much as a .204 going 4400 fps so let's not debate that issue. My question is, does anyone own one of these? What are your thoughts? I'm thinking this (in 9mm) will take out a groundhog with a head shot at least up to 75 yards. It would also be something good to have as a SHTF backup for silent hunting.

What's old is new again!
The Girardoni air rifle was used by Lewis and Clark!
Not quite as tacticool though!

I shot a semi auto pellet rifle and it had a real feeding problem. It had a magazine like the PCP's do and it would not pick up a pellet about two or three shots out of ten. I do not remember the make and model for sure, so I do not want to say what I think it was. 75 yards is very doable with a good pellet rifle.

I shoot 100 yards with my pcp .22cal

I don't have any experience with the semiautomatic air rifles but have used several different pcp bolt actions. I use a marauder and air venturi avenger almost daily