Hey all,

I know it may seem like a dumb question, but it’s relevant for someone living behind the iron curtain.

Can anyone verify if an Sig Spear upper is comparable with DPMS-style AR-10 lowers?

If someone has a Spear, AR-10 lower, and an MCX adaptor, can you speak to if the Spear upper at least appears to be able to feed and cycle with a DPMS lower?

Kind of don’t have access to anything right now, making plans for later but would appreciate help from someone who may be able to help. Thanks,
-Jono

From the looks of it I don’t think it will work.

Regular MCX has a different upper profile where the adapter they use won’t match to the .308 …