I once tested an Automag .22 MRF at the request of a gun store owner because the guy who had bought it from him said it was inaccurate. As I recall, it functioned reliably. However, it was very inaccurate. I only had a 2" .38 of my own with me at the time, as I recall. At any rate, that is what I shot MUCH better with just to make sure that it was the gun, not me.

Just one example, of course.