Anybody ever used this Rail? Mind sharing pics? Im thinking about picking one up.
- Thread starter bbyars
- Start date
Yeah i have not seen any pics of this rail on an actual rifle. It is expensive but damn, not even an image on google.
ill probably wait and get one on their holiday sales i guess. Ive never seen one in person or on the internet. I would of imagined them being popular for PRS type gas guns. kinda my plan. Ive had a mk8 and a mk13 as well but was curious if this one was a little bigger ID...
I have a Seekins hand guard system on my SPR rig. The flat bottom is great.
www.seekinsprecision.com
SP3Rv3 Rail System
Precision rifle stocks have a wide or flat bottom forend for stability, the SP3Rv3 from Seekins Precision brings this performance to an AR15 handguard. The design of the SP3Rv3 was born from experience shooting 3 gun and long range sniper competitions whe
www.seekinsprecision.com 
I think.... if you go to GarandThumb's youtube videos he had his MK18 configured with the G rail in one of his videos as a next step or in testing for the evolution of the MK18.
Might we worth browsing through or go to arfcom and thumb through some of their threads.
Might we worth browsing through or go to arfcom and thumb through some of their threads.
The OP is asking about the Geissele Rail designated Mk18 by G, which is a 16" rail with an Arca/RRS dovetail integrated into the bottom of it.
I have no idea why Geissele chose to name their PRS oriented rail "Mk18" but it does cause a lot of confusion.
16" Super Modular Rail MK18 M-LOK®
The MK18 is the latest in the line of Geissele Super Modular rails and is specifically made to interface with the Arca-Swiss Quick Release System. This product is bundled with a low-profile Geissele Super Gas Block, a $59 value, and an installation wrench, making the Geissele SMR MK18 a high...
geissele.com GarandThumb has a 9.5" Geissele Mk8 rail on his Mk18 rifle in that video w T-Rex Arms.
I've been eyeing one of the G Arca rails for a 224 Valkyrie upper, but am torn between that and a Seekins SP3R upper/handguard combo.
Well I feel like a bit of an idiot now haha. Thought he meant the G rail for the MK18.
Here’s some pics on my DMR built. I started with the Seekins but didn’t like the idea of a separate rail just to get ARCA and it didn’t feel right in the hand. Plus MK18 is 16’ long. Makes my 18’ barrel look small should cover a rifle +2 system(mine is rifle length. I can get you different photos if you want.
Also, wait till the BF sale.
Also, wait till the BF sale.
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I will try and dig up some pics. My teammate and I worked with Geissele to make the Mk18 to fill the roll in PRS Gas Gun. We use RRS dovetail on our bolt guns and wanted a streamlined solution for a precision gas gun. We also run 18-20" barrels and decided 15-16" was where we wanted the length. Overall I carry 18 plus pound AI AX rifles with RRS dovetail on the bottom and love the feel. I would say for run and gun with a 16-18" 3 gun rig, this may not be for you. For a precision platform it is outstanding but the PRS Gas Gun series fell apart and we have not been shooting as much gas gun stuff as we used to.
-Matt
-Matt
I have 2 of these and love them. Will see if i can dig up so pics to post. As mentioned wait till they are on sale and buy them.
Anyone know of any in stock right now?!? I am looking and cannot find one.....
I have the Seekins rail SP3Rv3 like an earlier poster mentioned and added an Area 419 arca rail to the flat bottom. Very happy with this set up.
If only Geissele would make this handguard for the DPMS/LR308 platform...it would be perfect in my opinion. I still may have to find one for another small frame gasser.
There is too much varience and every large frame worth owning uses a differrent interface (sr25, 417, MWS , Larue).
Now LMT needs to make a long mws upper with arca built into the bottom.
Can you post some pictures? I picked up one of these rails with the idea of using it on my RPR.
#1 - This is not an easy DIY project. You'll need access to a lathe and the skill sets to use it.
#2 - No permanent modification to the receiver is necessary, just the handguard. The Ruger barrel locking system is effectively removed.
#3 - The Handguard will be permanently modified. Gotta cut the centering... ears off at the lower rear of the handguard.
#4 - This process will effectively work for any AR-15 based Geissele Handguard/Rail
#5 - If using a RPR designed barrel, it will be permanently modified. The shoulder must be removed.
#2 - No permanent modification to the receiver is necessary, just the handguard. The Ruger barrel locking system is effectively removed.
#3 - The Handguard will be permanently modified. Gotta cut the centering... ears off at the lower rear of the handguard.
#4 - This process will effectively work for any AR-15 based Geissele Handguard/Rail
#5 - If using a RPR designed barrel, it will be permanently modified. The shoulder must be removed.
- I used a Criterion 26" .308 barrel with the AMU profile and salt bath nitride finish; I filed the shoulder off to prevent heating/warping vs grinding; I don't doubt a lathe would have been a cleaner better option. It took a while but was ultimately worth it. You could just get a normal barrel with the right receiver threads to bypass this process.
- I had to cut the ears off the rear of the Mk18 Handguard/Rail as the RPR receiver is wider than the AR-15 receiver it is designed to work with.
- I initially used the supplied Geissele Barrel Nut that came with the handguard and a Patriot Valley Arms thread reducer from Patriot Valley Arms. However, the barrel was VERY not straight and could easily be seen canting to the right against the handguard by 3/8"+. To resolve this I had a local Gun Smith create a new barrel nut out of some aluminum stock and it straightened right up.
- While everything was apart I lapped the lugs. Why not, right?
- Gun shoots 1/2" MOA pretty easily with my version of M118LR (175gr SMK, 43.5gr RL-15, CCI-BR2, Federal brass... because I had a bunch of once fired GMM).
- While I have not done it yet, I STRONGLY advise to get some M1913 Picatinny accessory to place over the handguard to receiver break to act as an additional locking mechanism. I haven't been tough on the rifle by any means, just to the range a couple times to test. However, I could pretty easily see how it wouldn't take much torque to hurt headspace.
I think that pretty much covers it.
Attachments
The barrel nut is what makes or breaks the build. Be careful on the inner diameter as the threads are a touch smaller than the remainder of the inner diameter. And you can't get too big inside either for the bolt recesses on the outside.
GL! I look forward to seeing how your project shakes out.
GL! I look forward to seeing how your project shakes out.
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