I would check the magazine.
I've shot Winchester value packs, Federal, S&B, Remington, American Eagle, etc, and the only times I had repeatable problems was not because of ammo, rather it was cheap aftermarket mags.
I'm currently shooting a P99 and a Luger LP08, and both guns love the S&B, followed by the Winchester. The Remington seems OK as well. The only ammo I've had FTF's with, in the good magazines, has been the bulk Federal (Walmart stuff). But even that is few and far in between.
Get a MeGar magazine and see if you still have problems. MeGar seems to be the most consistently reliable magazine maker out there.