Fitting CMR rail onto Marui M4

[-Archer-]

Hi guys, just got my Centurion Arms CMR Rail in the post today, have started to put it all together and hit a bit of a snag.



As you can see, the barrel nut won't tighten any further on the thread, and that little nub on the receiver gets in the way of the rail so it won't fit in place.

im hoping that the barrel nut wont be an issue, but the nub definitely is, so I'm thinking maybe just lop it off with my dremel? Would that be the best course of action or is a necessary part of the receiver?

Any advice would be appreciated!

[Hef legend]

Re: Fitting CMR rail onto Marui M4

That nub isn't on any of my receivers as far as I can tell. It looks like the spot where a gas tube would go, guessing your rifle didn't have a fake gas tube etc

Personally I'd say remove it, doesn't appear to be structually important.

As for the nut not threading all the way on, once you have it on a tight as it will go, do you have any movement in the outer barrel?

[-Archer-]

Re: Fitting CMR rail onto Marui M4

The barrel is locked down tight with no wobble at all so think that aspect should be ok.

Yeah I think i'll remove the nub, thanks for your help!