I'm surprised to hear about these being finicky. Walther did have to revamp their mags several years ago, so if you have the old mags that could be part of it. You should be able to google it and get the part number for the improved mags. If you can't find it, let me know and I'll get into my safe and get the info to you. I've owned 4 of these and other than the first which had the old mags, they have all functioned great with all ammo from CCI to any bulk to Remington subsonic.