PITA having your ammo dictate that you're going to practice clearing a particular malfunction! I'm curious how that happened though. In my experience, 'double feed' malfs involve a bad extractor.I loaded up 10 rounds per magazine of 10 magazines to perform a specific drill. I got through one magazine of the ten without having double feed type malfunctions. I then tried it with two other guns and had the same problems. Went back to my normal practice ammo American eagle 147 grain and had no problems whatsoever.