Valk magazines for 6ARC?

I've read elsewhere that some guys have had success using 6.5 Grendel, the parent case for 6ARC, in 6.8SPC mags, but I don't recall the intended mag capacity or how many rounds of 6.5G they could get to successfully stack and cycle in the 6.8/Valk mag.

Only way to find out will be to try it in your rifle with your mag(s) and ammo. You might get lucky, or you might chew up some meplats :)