I took my Sig P220ST to the range today to give it a workout. I fired one hundred rounds of FMJ without a hiccup. I then switched to 230gr Hydra-Shoks to test reliability. Everything was going well until I got to last eight rounds. I fired five rounds with no problem, but on the sixth round the Sig would not discharge after pulling the trigger. Pulled the trigger again for a double strike and still no discharge. I removed the magazine, and attempted to clear the Sig by racking the slide. The slide would only move back about 1/4 of a inch! Locked tight! Needless to say, I spent about two minutes going through an abbreviated tap/rack drill, with the Sig pointed down range of course. Finally, I decided to ask a range officer for some help (I've never experienced this type of jam before). I explained what had happened and he saw for himself how locked up the Sig was. He then suggested that I try firing it now. Well, to my surprise the damn gun discharged! The range officer told me that apparently the abbreviated tap/rack drills may have reseated the round to enable the firing pin to strike the primer. I went ahead and finished up the last two rounds and called it quits for the day.
What concerns me is 1) Did the abbreviated tap/rack cause any damage to the inside of my Sig?, and 2) How could a round that was mis-aligned with the firing pin and improperly seated to the point where it couldn't be ejected, discharge nonetheless?
What concerns me is 1) Did the abbreviated tap/rack cause any damage to the inside of my Sig?, and 2) How could a round that was mis-aligned with the firing pin and improperly seated to the point where it couldn't be ejected, discharge nonetheless?