Does the Geissele Mk4, Mk8, and Mk18 all use the same barrel nut?
- Thread starter Theanswer4
- Start date
I believe so. It's their own proprietary barrel nut.
Thanks! I was just wondering because the website pics show the Mk18 has a different nut but the pdf drawings all have the same part number. Does Geissele not answer their phone anymore?
Unknown. I got my Mk4 handguard a good while ago and love it. No need to contact their customer service for anything.
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If I’m trying to figure out if the barrel nuts are the same it would be helpful if they answered.
The mk4 and mk8 do. No idea on the 18. The mk13,14,16 use the smaller nut that does not work on the mk1,2,3,4,8. The 18 looks conflicting on their site. The pic of the rail has the bolt holes horizontal and that would indicate the larger nut of the mk1,2,3,4,8. But the picture of the nut itself is the smaller one, used on the mk13,14,16.
I wonder how many of those MK16 rails have bent. I screwed up and thought it was the MK18 rails that were bending and bought a MK16 instead. I'm really going to be pissed if that cheap ALG rail I bought for my pistol build holds up better than the more expensive Geissele MK16. 
But then again, I'm not a youtuber that goes around throwing my rifles around anyway.
But then again, I'm not a youtuber that goes around throwing my rifles around anyway.
I'm really going to be pissed if that cheap ALG rail I bought for my pistol build holds up better than the more expensive Geissele MK16.
The ALG rails are neither slim not ergonomic, IMO, compared to a lot of other rails available, but they are solid & the mounting system, though a bit of a pain to install, is as solid as there is available other than something like the URX.
I don't throw my guns on the ground or stomp on them either, so I'm hoping the MK14 I have holds up....................been using SLR's with no issue, but decided to give the MK14 a shot.
MM
Installing the ALG wasn't a pain at all. Just not sure why anyone uses a barrel nut that requires timing anymore. It actually seems cheaper and easier to make one that doesn't require timing but I could be wrong.
It may not be the thinnest but I don't exactly have short fingers either do it's no big deal to me. I also have a SLR hand guard on my 308 and I love it. They make great stuff and they gave me great customer service. But my pistol was not supposed to be expensive. I think I might've failed on that part though ???
It may not be the thinnest but I don't exactly have short fingers either do it's no big deal to me. I also have a SLR hand guard on my 308 and I love it. They make great stuff and they gave me great customer service. But my pistol was not supposed to be expensive. I think I might've failed on that part though ???
Yeah, project cost over-run................BTDT, maybe more than once.
MM
MM
I like G's stuff. But I'm also not a G fanboi. The Mk16 bendgate is horribly overblown. Hang heavy shit on the end of a long thin aluminum rail, and it will bend with sufficient impact force. Physics is physics. The bending report started with a MAWL being hung on the end of a 13.5 Mk16 that was thrown onto the ground. The MAWL unit, at the end of the 13.5 inch rail, was creating sufficient force such that the GB was impacting the rail.
Perhaps more importantly, reports from a reliable poster (over on a large ar15 site) who has first hand knowledge of the Mk16's field use with some high speed dudes running URG-Is reports exactly ZERO issues with them. Your Mk14 will be fine.
As an aside, I have an SPR build with a 13.5 Mk16. I have an SLR GB underneath it. Zero issue or evidence of impact.
