I have brought my 43 to the range 3 different times and had the same issue. It was double feeding and just not cycling right every few mags or so. The mags are brand new. The entire gun is stock except the sights. And ideas I read a few things about 43s jamming and double feeding online. Any suggestions. Also I called Glock they told me to bring it to a certified Glock armorer and they would pay the bill. Any good certified Glock armorers around the Boston area north shore. They have to be certified.