i tried to post a picture but this website keeps making my computer freeze up. if you google it, it is model number 811013. it has a rail on top for optics/BUIS and thats it. plain jane model
I have the same rifle and the same issue. There's a threaded hole in the area where I would expect the front swivel to go, don't know what it's for if not for that. Maybe someone here has the answer.
I e-mailed S&W with that question when I got my first M&P-15 ORC. They responded that yes, that's what the threaded hole was for.
I never bothered to try to find out what the thread turn-ratio was as I have since installed a Quad Rail forearm and a Midwest Industries sling attachement to the forearm.
Not to hijack the thread, but is the factory forearm good and tight on your M&P-15 ORCs? Mine was a little loose and so is the new rail forearm I put on. It has a little up and down play because it isn't very tight right where the retainer ring is located behind the gas block. It's to the point that I certainly couldn't mount a laser or other sight on the forearm because it has too much play.
I think my ORC is one of the first. I saw a new one a few weeks ago and it looks like they might have found a way to make the connection more rigid.
mine are on there tight. and thanks for answering my question. wasn't sure if i was supposed to use the threaded hole or the other hole for the sling mount.