2 of the factory original Mec-Gar mags I've had in my P-11 rattle when you get the 9th and 10th rounds in the pistol. If I wasn't anal about the rattle, I could just leave it well enough alone, as you can't hear it when in the pistol and concealed.
I normally load the magazine with one, chamber that one...drop the mag and fill with the next 10. When finished, turn the mag so that the rounds are facing up and lightly tap the back of the mag against your other palm. The rattles usually go away with one or two taps.
As I recall, there was another fix on the KT mags you could try, although I don't remember if it was for the rattle prob. Someone basically came up with a piece of wire that would hook into the mag, going the length from top to bottom...this would properly space the rounds. Please forgive me if I've confused this fix with another problem.
Alternately, you can try the S&W mags that fit the P-11, although I forget which model number they are.
Travis
