At that frequency, there's nothing you're doing wrong. If you've had <0.2% issues over time, those are more than likely just freak accidents. I understand they suck, but, generally, what accident doesn't suck?
There shouldn't be an explicit need to change bolt head components each time there's an issue. If you are unsure, you can send pictures for visual inspection or just try running the same components and make a decision after a few rounds have been cycled.
Overall, it's not likely that you have an issue that needs to be addressed. But, if you're looking for something to do, you can shim your magazine to avoid any fore and aft rocking. Folks have used anything from electrical tape to velcro tape to solidify the magazine's fitment in the magazine well.
Vertical fitment is important but, again, with so few issues, yours is likely in a good spot. You're looking for no more than 1/16" of vertical play with the bolt open or out of the action. Generally, it's about .100" from the top of the highest position of the magazine latch.
If you've got questions, let me know
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Thanks - Ray