Yep, semi-auto single shot! Picked this up off Gunbroker and it arrived today. Neat little .22 and pretty unusual. Fires from an open bolt, and ejects the empty out the bottom (making it a "semi-auto"). Every time the action cycles, it automatically puts the safety on, so you have to take the safety off for each shot. Probably make a good training rifle for first time shooters. They were only made from 1958 to 1961. Here's a Youtube of one.
[video=youtube;7qjs8Z0CxWM]https://www.youtube.com/watch?v=7qjs8Z0CxWM[/video]
And here's mine.
[video=youtube;7qjs8Z0CxWM]https://www.youtube.com/watch?v=7qjs8Z0CxWM[/video]
And here's mine.