bluntly, if it works with other ammo, just don't use the magtech with your gun. semi autos of ANY caliber can be ammo sensitive. Most range ammo today is made so inconsistently across brands that some brands just wll NOT work with a given gun. Also critical duty/defense is known for those problems in a LOT of guns as the rubber/plastic tip insert tends to cause friction and can jam up on the feed ramp

also you said most problems were with the 7 round mag? have you thought about grabbing another magazine to make sure you don't have a mag feeding problem?