[fifthward]

I use a channel grip, generally, and I'm looking to thin down the grip on my Scar.
The PMM keymod rails seem enticing, to do the task.

The only downside I see is replacing the front barrel attachment screws, with integral detent. But I'm not planning on really switching out barrels a lot.

Is there any reason not to go this route??

Thanks in advance.

 

[chainring]

If you want to trim width, maybe look at the Kinetic Development Group MREX. More expensive, though..

 

[fifthward]

If you want to trim width, maybe look at the Kinetic Development Group MREX. More expensive, though..

Thanks. I read about the MREX, and watched the vids. Yes it is expensive, and it also involves taking off the heat sink lower pic rail.

I've been hunting for any negative reviews on the PMM Keymod...and no dice? Do you happen to know any issue with QC, anything - as I'm about to pull the trigger!

 

[chainring]

I've got no experience with the key mod rails, but I've got their selectors waiting for my 16 and the craftsmanship on those small parts looks great.

 

[DrToyHoarder]

Love mine, very nice quality.

 

[fifthward]

Love mine, very nice quality.

Good to hear! I'm close- but now this MREX has me thinking!

Do you tighten all the screws to mount, to the 62 in. Lbs??

 

[Jarod Legsdin]

Good to hear! I'm close- but now this MREX has me thinking!

Do you tighten all the screws to mount, to the 62 in. Lbs??

fifthward, Jrod here from PMM, The only bolts that are required to be TRQ'd are the barrel bolts, They are also locked into position with a Allen screw from the top to keep them from backing out. The MREX is a very nice extended handguard, I like to keep my rifles short so that is why I came up with my KM rails. It really comes down to the user's needs.

 

[fifthward]

fifthward, Jrod here from PMM, The only bolts that are required to be TRQ'd are the barrel bolts, They are also locked into position with a Allen screw from the top to keep them from backing out. The MREX is a very nice extended handguard, I like to keep my rifles short so that is why I came up with my KM rails. It really comes down to the user's needs

Allen screw from top? Well that's a nice touch. Would you recommend loc-tite for the two front screws that attach the barrel?
Thanks for info...I'm going to decide here within the day - either the keymod or go for broke and get the MREX.

 

[Jarod Legsdin]

Allen screw from top? Well that's a nice touch. Would you recommend loc-tite for the two front screws that attach the barrel?
Thanks for info...I'm going to decide here within the day - either the keymod or go for broke and get the MREX.

To the best of my knowledge and after evaluation of the Barrel locking bolts it seems they don't use any use a Loctite, However the standard M4 Rail bolts use either a loctite 603 or 609. Both are good and have high heat resistance, I supply both loctite 603 and 242 with my rails and advise the use of them on specified bolts in my installation instructions.

With that Said In my Testing (See PMM Range day CQC 10" 16) I ran close to 1000 rounds through that rifle with no loctite on any of the hardware including my barrel bolts, As it was a test and I was interested in verifying TQ specs after with both thermal expansion and contraction taking place. The bolts were solid and GTG.

The set screw simply replaces the factory spring loaded locking detent mechanism on the T25 Torx bolt, that little detent spring inside of the plastic rail does one thing it keeps the bolt from backing out once TQ'd down, the same applies for the Allen Screw in my Rails.

Hope that helps.
~Jrod.

 

[Fnpurist]

Allen screw from top? Well that's a nice touch. Would you recommend loc-tite for the two front screws that attach the barrel?
Thanks for info...I'm going to decide here within the day - either the keymod or go for broke and get the MREX.

give PMM your business, he's a good forum sponsor.

 

[rsmurdoch]

Changing to Keymod rails takes all that quad rail bulkiness out of the forend. It really allows for a great grip.

 

[fifthward]

give PMM your business, he's a good forum sponsor.

I hear you. I already picked up the rear QD mount from PMM...and it is top notch. I'm leaning towards the PMM keymod, and running Noveske panels, as I'm familiar with them on my AR builds (piece together )...this will be 100% functional. Or - go pure sexiness with the MREX.

I'll decide here shortly with some late night research as the kids sleep, and make purchase by morning.

Thanks for all the advice/input.

 

[thmpr]

The only reason why I am sticking to PMM's version is the adequate space needed. The MREX is too long for my use.

 

[thmpr]

I hear you. I already picked up the rear QD mount from PMM...and it is top notch. I'm leaning towards the PMM keymod, and running Noveske panels, as I'm familiar with them on my AR builds (piece together )...this will be 100% functional. Or - go pure sexiness with the MREX.

I'll decide here shortly with some late night research as the kids sleep, and make purchase by morning.

Thanks for all the advice/input.

Have you checked KAC KM panels? Sold my Noveskes for these.

 

[ORSalesRep]

The MREX looks interesting for my SCAR16, but I have a 10.5" barrel and it looks like it will not work in that application. Am I wrong?
SB

 

[chainring]

Unless you are going to put a Noveske Kx5 on your 10.5, even the 4.9 inch MREX would extend past your muzzle, ORSALESREP.

As for Keymod rail covers, take a look at the RailScales at getrailscales.com

 

[baileyscar]

I ordered the key mods they feel great and awesome quality just make sure you have help or a gun vice when torquing the barrel bolts I striped mine

 

[chainring]

Is it that hard to torque them? Use the appropriate setting on a torque wrench has never failed on other rifles - is there something different about the scar in that respect?

 

[fifthward]

My SCAR barrel boots came out just fine - and I also just picked up a Borka 62 in/lb torque wrench.

For those interested, I went with the MREX (Cry once!)

Thanks for all the info, and advice.

 

[chainring]

Post pics, looks like my 16 will be here next week and my MREX about the same!