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Mega Arms MKM

sentry1

Crayon Eater
Full Member
Minuteman
Jul 7, 2012
1,991
5
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Madison, Alabama
I'm waiting on a MATEN ambi matched set from the group buy, but in the meantime, I found a great deal on a MKM rifle length upper.

I'm still in need of a lower, but I can wait on the group buy. Anyway, what are your thoughts on the key-mod handguard? It's definitely much cheaper than some of the other large frame AR handguards.
 
I like how the MKM upper is available at 14" IMO, MKM uppers are better than going for an aftermarket handrail. Nevertheless, I still rather have the old monolithic upper receivers. The monolithic uppers I have just seem stronger.

Back to the topic, you could find an MKM upper for $5XX. Your upper that your waiting on sells for $3XX, basically, that's $2XX for the hand rail. I think it's a good deal.

 
I agree it's definitely a cost effective option on the handguard, especially when one can find the MKM upper sub-$500. What about key-mod accessories, are those easy to come by?
 
I haven't found it necessary for additional rails. It already coems with one, so I use it for the bipod...it's a nice design overall.
 
I agree it's definitely a cost effective option on the handguard, especially when one can find the MKM upper sub-$500. What about key-mod accessories, are those easy to come by?

The Noveske Key-mod rails and accessories fit on the MKM.
Also the MKM comes with one 9 slot rail.
 
The Noveske Key-mod rails and accessories fit on the MKM.
Also the MKM comes with one 9 slot rail.

In case it matters to anyone, there's indication elsewhere on the 'net suggesting that Noveske's NSR rail panels do not fit the MKM. I think keymod accessories are supposed to fit any keymod rail, but NSR accessories might fit only the Noveske NSR rail.
 
The Noveske Key-mod rails and accessories fit on the MKM.
Also the MKM comes with one 9 slot rail.

I wonder if anybody makes a longer key-mod rail? The longest one i've seen is about 3" or so...I wonder if AI offers some, the AX rifle has a key-mod rail...?

P.S, thanks for the scope! It looks nice on my MKM :cool:
 
In case it matters to anyone, there's indication elsewhere on the 'net suggesting that Noveske's NSR rail panels do not fit the MKM. I think keymod accessories are supposed to fit any keymod rail, but NSR accessories might fit only the Noveske NSR rail.

I don't know why there is that indication, maybe to help sell more manufacturers accessories (instead of everybody buying the least expensive one?)
I have both the MKM and the NSR and everything fits on each other.
Like you said, i would think all the keymod styles would be the same...why they would want to make it proprietary, is beyond me.

I'll double check with micrometer on each rail though.

I wonder if anybody makes a longer key-mod rail? The longest one i've seen is about 3" or so...I wonder if AI offers some, the AX rifle has a key-mod rail...?

P.S, thanks for the scope! It looks nice on my MKM :cool:

No problem man. Thank you for the trade brother!
 
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Okay, I just measured the MKM and the NSR side by side

The keyhole on the MKM measures 0.6885" (from top of keyhole to bottom) and the NSR measures the same 0.6885"

the spacing between the keyhole to the next keyhole a tiny bit different.
MKM being 0.0990" and the NSR being 0.0955"

However, the noveske 4 slot, 9 slot and QD swivel accessory all fit on the MKM without an issue.
I have not tried the light mount or the polymer panel handguards.

ETA: i measured with a cheap harbor freights digital micrometer, so don't quote my exact numbers.
 
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I don't know why there is that indication, maybe to help sell more manufacturers accessories (instead of everybody buying the least expensive one?)
I have both the MKM and the NSR and everything fits on each other.

Second post on this link indicates that the NSR panels do not fit properly on the MKM:

Sneak preview....

I own neither the MKM nor the NSR, and not affiliated with either; just researched each to some degree. Please set me straight if my info is flawed.
 
Drifter,

After reading your link and thinking about the measurements i just posted above...I would imagine that the longer pieces (i.e. Noveske polymer panels)...may have trouble fitting on the MKM. Those panels i believe snap into 5 keyholes lined up.

But the shorter 4 rail piece only fits between 2 keyholes and the 9 rail piece fits between 3 keyholes...AND i have had no problems with it.

So...again going back to the measurements above...2 keyholes measured from end to end on the NSR vs MKM is very very little (like .004" - .008" difference). BUT measuring 5 keyholes from first to fifth would make a growing difference between the NSR vs MKM (like .02" - 0.024" difference).

I've been slow to order the panels but when i do...i can try them on the MKM and see what the problem is.
If you have any questions about it or need pictures seeing the differences, please let me know.

Respectfully,
Original_Copy
 
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The NSR Polymer Keymod panels line up correctly but the "key" thickness must be thinner on the NSR rail as when I tried to use the panels on my MKM the would not snap in place. MKM must be just a tad thicker; managed to force one on but couldn't get the others on.

NSR sling swivel works fine as it uses a screw to tighten the key to the rail.
 
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There is a couple of mega mkm uppers on gunbroker and like green338 said for 500 bucks i dont think that is a bad deal at all. One of them was even buy now for 515.