Removing BCM KMR rail for installation of IWC keymod bipod mount

SilverBullet432 · March 28, 2014, 4:19am

yea man, i had been waiting 2 weeks for it to ship!!!

krichbaum · March 28, 2014, 9:50am

Koshinn:

The Noveske trx bipod is perfect for keymod, I’ve been running it for like a year or so, it’s completely rock solid.

It comes with the stud, a hat shaped plastic piece, and the backing plate. Slide the backing plate into place over a large keymod hole, with the raised portion facing towards the barrel, not towards the rail. Put the hat shaped plastic piece facing towards the keymod hole (which is upside down from how it normally mounts to a troy rail) and then screw in the bipod stud. To get it aligned, attach a Harris bipod or insert a punch into the hole and gently turn it until it’s aligned. I’ll take a picture.

With bipod mounted, super low profile!

See how the threaded backing plate has the raised portion towards the barrel? Also notice that the screw part of the stud is basically flush with the backing plate’s threaded hole, implying a lot of thread contact.

The plastic hat is upside down… you can’t see the top of the hat in this picture since the top is inside of a large keymod hole:

Overall it’s very stable and isn’t going anywhere. There’s enough torque (using the plastic as a crush washer essentially… But only enough torque to align it after it’s hand tight) that it’s not going to move when the bipod isn’t mounted, and the way the bipod works, it physically can’t come out if the bipod is mounted and tightened down.

That being said, the IWC version is much cheaper. But at least the Noveske one doesn’t require removing your rail, which is only a minor inconvenience anyway.

Thanks. I did install it like that and barely had any thread engagement between the stud and back plate. I went ahead and tightened it up some more, and that plastic piece is pretty well deformed but as long as it doesn’t crack it will definitely be ok like that. I just didn’t think that plastic piece would stand up to that. Yours doesn’t look deformed like mine and I can see that you have plenty of thread engagement. Mine is on a KMR rail FWIW, not sure what the difference is. Anyway I’ll let it ride like it is now.

Sorry for the thread hijack.

Slippers · March 28, 2014, 1:37pm

Almost sounds like you have the plastic piece on upside down. It should rest against the backing plate within the large part of the keymod slot.

krichbaum · March 30, 2014, 11:26am

Nope. But I did figure out what the difference is. The NSR rail is flat on the bottom, inside and out. My KMR rail has a round profile on the inside…this matters. When trying to install the Noveske stud the way Koshinn describes, the backing plate sits further away from the rail’s outer surface due to the curve. I ended up flipping the plastic piece so that it doesn’t index in the keymod slot, and flipping the metal backer so that it indexes in the slot from the back side. This way, I get good thread engagement without torquing the crap out of it.

Bad:

Good: