10.5" SBR NOVESKE (VLTOR) MUR 5.56mm Upper vs. Gen III Upper

[Armadillo]

Is the older VLTOR MUR upper receiver as good as the Gen III upper?

They are both about equal in price but I'm wondering if I should avoid the VLTOR MUR since it is older.

It would be for a Gen III lower.

[markm]

but I'm wondering if I should avoid the VLTOR MUR since it is older.


Was there an issue with "older" MURs?

Gas port size would be my biggest concern. Last 10.5 I saw from Noveske (the FSB version) had too large of a gas port.

[Armadillo]

Was there an issue with "older" MURs?

Gas port size would be my biggest concern. Last 10.5 I saw from Noveske (the FSB version) had too large of a gas port.
There was never an issue as far as I know about older MURs.
I was just thinking that maybe the Gen III was an improvement.

What was the problem with the gas port being too large?

How does that affect the rifle?

[3ACR_Scout]

I seem to recall that there was an issue that some people had with certain types of rail systems not interfacing well with the MUR upper. I believe because of its beefed up shape, rails that had bolts that extended past the front face of the receiver might not fit on the MUR upper, like Daniel Defense and maybe Larue. I don't know if the Gen III addressed that, but I don't think it was ever a function / performance issue with the MUR, just a question of fit.

[Armadillo]

https://www.vltor.com/shop/ar/upper-receivers/mur-modular-upper-receiver/

The MUR is a rigid Mil-Spec flat-top upper made to fit all AR15/M16 M4 rifles and carbines. The MUR was developed to give the customer a Mil-Spec correct upper receiver with a thicker wall, making the MUR upper receiver a stronger platform. This more rigid upper receiver will increase accuracy and reliability, while extending the life of the interfacing components. The MUR-1A model comes equipped with a shell deflector and forward assist. The MUR-1S comes with a one-piece machined shell deflector only.

FEATURES:

Aircraft-grade aluminum construction
Machined from 7075 Forging
Stress relieved, heat treated, aged twice and cryogenic treated
Hard coat anodized, black per MIL-A-8625 TYPE III Class 2
Precision machined and finished by hand
Bore coated with dry film lube over the anodized surface
Compatible with all Mil-Spec AR-15 parts and accessories
Available with (MUR-1A) or without forward assist (MUR-1S)
M4 feed ramps

Maybe if it's more durable that is a good thing.

[ndmiller]

I like the Noveske marked MUR as opposed to the non-marked MUR as it has the anti-rotation hole for certain hand guards.....If that matters to you.

[sig1473]

Noveske MUR is forged while the Gen III is billet. I've got a Noveske MUR that I tried a Fortis REV on but I had to shave off the anti-rotation tabs. I eventually took it off and put on a Geissele MK8 which fits nicely.

[markm]

What was the problem with the gas port being too large?

How does that affect the rifle?

Over gassed with a suppressor attached. And just too much unnecessary recoil from excessive bolt speed.

[nightchief]

I have two MUR-1A uppers...they are machined very well. I'm using plenty of FCD parts in conjunction with mine with no issue. They have a snug interface with the barrel extension. Work with LaRue Pic/MLOK/Skinny hand guards and Geissele Mk4/8 hand guards with no issue.