Just discovered my KVP bolt had sloppy loose gas key screws. 1st indicator was a fairly stiff dragging when removing the bolt from the NFA billet upper. I had wiped it down prior to the Monday match and it seemed fine, although I didn't really pay much attention to the gas key.
The bolt was slightly beat up in front of the gas key, where the side charging handle lug mates with it I believe. I smoothed out the slight burr that had formed there with a file. It looks as if the burr was dragging in the upper on the edge of the gas key channel.
I red-loctited the screws, torqued them as much as felt comfortable and attempted restaking. We'll see how it goes. May not get to try it before the Sunday match.