is it shooting ok for you so far?I have the KAK 300 WSM upper on a LR308 lower and it is really only viable if you reload. The issue is that the max OAL of the .300 WSM is 2.860 in while for the .308 it is 2.800 in. You wouldn't think that 0.06 in makes much of a difference, but it does. All the commercial ammo I've used is loaded out to the max OAL and therefore has trouble feeding through most AR10/LR308 mags. The only mag that works even semi-reliably is the ASC Stainless Steel SR-25 AR10 .308. I find it easier to reload it down a bit so the OAL is closer to the .308. Also, the case dimensions of the WSM are such that you can really only load 4 cartridges into the mag if you want to reliably feed that first round. When everything is working right, it is a remarkably powerful and accurate rifle, but it is a bit of a PITA to get everything right.
i looked at some reddits and it seems the issue there may be with an extractor that is apparently one of a kind with no simple way to source the replacement?
no issues so far with yours, i hope?