Welrod and its clones are bolt action. There's a knob at the end that needs to be twisted, pulled, then pushed back in and twisted back to lock again. They're a

Welrod and its clones are bolt action. There's a knob at the end that needs to be twisted, pulled, then pushed back in and twisted back to lock again. They're also rather tubular looking, ironically unmistakable at this point. Any suppressed mag-fed handgun will have a similar geometry as a Welrod/VP9, like how every laptop will look like a MacBook.