They should move easily, with very little force. You might try soaking in Kroil for a few days. The do unscrew from the barrel by putting 1/8th pins through it and turning with a wrench or similar. There is a little square piece and spring in the front that engages a notch in the outer sleeve. And yes, they do work. Not as well as some others like a Vias or Score High, but it is very noticable.