I just ordered this upper and it says that it will not accept an anti-rotational rail system. I’m looking for a 12" (+/- a couple inches) quad rail to go over a 14.5" carbine length barrel. No FSP
Thanks
Jeff
I currently have a DD Lite rail on my MUR upper. It is a fantastic system. A little pricey but rock solid and very high quality
is the Centurion C4 considered anti rotational? That is IMO the best quad rail on the market and comes in 12" as well. Just not sure if it is considered anti-rotational.
The Midwest Industries Gen 2 SS and T-series will both work, because their indexing is purely on their barrel nut and doesn’t extend into the receiver area. They are also lightweight, inexpensive, and as far as I call so far with my Gen 2 SS, well made.
The YHM handguards would also work but are not quite in the same league, IMHO.
I believe all the Troy one-piece options have an index tab and therefore won’t work. So does the Midwest Industries two-piece gen 2 quadrail.
Noveske NSR or KAC URX 3.1
This is what Noveske said about fitting a Centurion rail.
“To fit the Centurion rail you will have to dremel off the two little tabs that hug the upper in the very front.”
Yep,
Just did some research myself. Didn’t know Noveske’s MUR differed from Vltor’s. Notice the recess cut out at the front of my Vltor MUR:
And from the ejection port forward Noveske’s is flat:
-Jax
Hmmm. Never knew that. Thanks
I would sell the Noveske upper and get the Vltor version. I don’t recommend grinding off the Centurion rail tabs.
The Noveske MUR also differs because it has a hole drilled out for the anti-rotational pin used in the SWS and NSR rails.
I’m having a hard time finding anything right now. This stuff is going on the shelf till everything goes back to normal.
Yep, was familiar with that (I have a Vltor MUR w/a NSR attached) I just didn’t know there was any exterior dimensional differences.
-Jax
I posted about it a few months ago, but it was in a custom build thread so not many people read it 
I’m sure people posted about it before me too!
I also found out there was an earlier MUR with a differently shaped forward assist, it was more slab-sided and not as sleek looking. Maybe that was the billet MUR?
Off topic but what mag release button is that?
I think you’re referring to the Vltor lower receiver, so Vltor.
MM did a write up on the change that Vltor did some time in 07, the forward assist housing change happened some time in 09.
So Noveske is using pre 07 mur receivers but with the post 09 forward assist?
Vltor had to change the design to accommodate the anti rotation tabbed handguards. Our version is the original design with pin hole anti rotation.
The cosmetic change to the FA happened separately and went on all the MUR/VIS.
I like the extra meat on the Noveske.
I received my Noveske MUR today. I’ll take some pictures when I get home