I was playing with a Ruger MkIII 22/45 this weekend and noticed an odd thing. The slide/bolt stop did not disengage when retracting the bolt with the magazine out. Upon further inspection, I found the bolt stop did not have any spring tension on it so when the magazine is out and the bolt disengaged there was nothing to cause it to drop away, which would be the same case chambering a round. I don't remember from my previous experience with Mk I, II's etc. Is this normal or was this one missing a spring? I've grown accustomed to slide/bolt manipulation instead of using slide stops.