Quote Originally Posted by JeepsAndGuns View Post
It can change it very little on some cartridges, and a little bit more in others. However unless you are at or near the max load, it should not be much of a issue.
The best thing you could do is load some up yourself and try them. I would reduce your load a little and work back up. That way you will know what and how much you need to change your load when/if you need/want to change to the mag primers.

I also did a test myself on pistol rounds and did not see a huge difference.
https://www.ar15.com/forums/armory/S...ts-/42-518085/
That was interesting data ... thank you for the link.