Remember the song Feeling Groovy? Here let me plant the ear bug for you.
Slow down, you shoot too fast.
Got-ta make that ammo last.
Shootin' down the latest stage.
Lookin' for points and feeling groovy.
Ba da da da da da da, feeling groovy.
Thursday we shot a new USPSA classifier, Can You Count CM 06-03. It's a hoser. 2 targets, one at 4' and at 8'. Yes that's feet. 5 shots into one, reload 5 shots into another. (Repeat for a second string.) Evidently I was shooting a little too fast for my 929. Pictured below is my moon clip. The single round is not a misfire. The locking lug didn't catch the cylinder, which I must have pulled the trigger so fast that its inertia spun the cylinder on around to the next chamber. I didn't notice this when it happened. And I didn't think I was going that fast. My total time for the two strings was 14.96. Hit Factor was 6.6845 for a high C, 58.47%. For those slow of with math, that's 2 draws, two reloads and 20 rounds.
With my 686's I do practice speed runs with the goal of 6 shots in <1 second. And I've done it with the 4", 5" and with the just repaired 6". In fact my record is 0.94seconds. JM isn't threatened. My 629 need more tuning as I'm only at 1.02 seconds. But I don't practice this with the 929, evidently I should. With it's titanium cylinder I wouldn't have suspected this would happen.
Yes, I know what to do. Check the locking lug to make sure it's not worn or damaged. Replace the spring. Clean the exterior of the cylinder really good and check for worn or damaged slots.