I mostly use Magtech in my 650 without any issues except one, but it isn't the primers fault.
Do you ever have the issue where the decapper does not pop out the primer? It actually pops out the primer and pulls it back in but that is another discussion.
When this happens, the spent primer is still in the case, and indexes to the primer station. You push forward on the handle to seat a primer but the new primer bangs into the back of the old one because it didn't get removed. You reach in, grab the case and toss it back in the case feeder to go through the decapping process again.
When you pull the handle again, that "new" primer gets ejected into the little tray for recycling in with the new primers. Problem is, if you were putting a lot of force on that primer when you were trying to seat it, that primer is damaged goods and can get stuck in the primer tube when you go to pick it up again. I've seen this happen a couple times in thousands of rounds.