Welcome to the Forum

I just picked up a mk23 K100. I've got a mecanik mo2 that I'm not otherwise using that is the burris footprint and works with the optics plate labeled "1" that the gun came with. This plate uses the smaller pair of inset nuts for the optic mounting and all the optic mounting screws I have on hand are too big for those smaller nuts.

Before I haul off to the hardware store to try to find something, does anyone know what thread size those smaller nuts are? Thanks!