Just picked it up last night. frame rails show no wear whatsoever, however, the slide to frame fitment has a lot more play than any of my other pistols (Glock, HK, Kahr, Springfield). It's to the point where if I shake it from side to side there is an audible rattling sound. Since this is my first Sig, is this normal? I realize this is an older gun (KA - 1990) but I still don't think there should be that much play.