I can't say whether or not it would physically fit, cause I've never tried it. You've got to keep in mind that the large frame 308 AR is a different animal than it's small frame counterpart. There's enough confusion just trying to get the many different manufacture's to try and get some kind of standard. They're all out there doing their own thing for the most part. No Milspec on the large frame AR. Which is why we keep seeing cycling issues spring up, as guys come here trying to figure out why their rifle won't run.