So...I just did something without thinking it through properly. I had resized some brass with a neck bushing and primed the cases. I wanted to compare the same powder load but with a 1 thou smaller bushing. I did not take note of the decapping pin in the Redding neck sizing die. I do not use this for decapping and it was set 'short' but it still contacted the primers. Luckily I was doing things very slowly. It did not pop the primers all the way out but did partially unseat them - I'd say about 50%. I have managed to reseat them but now I'm wondering whether to use them or fire them (unloaded round) and start again.