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4/21/2014 9:35:35 AM EDT
What is the difference between the 13" rails offered by Geissele? This is for a custom build. The descriptions on their site are very vague and can't find a post that covers this. There is a lot mentioned about weight reduction and cheaper substitutions for the MK1, but at the expense of what? Cheaper materials? Strength?
MK1 vs MK2 vs MK3 vs MK4 vs MK5?

How do you guys like these rails?
Do you prefer Keymod vs the tapped holes to add rail sections?
4/21/2014 1:37:44 PM EDT
[#1]
Quoted:
What is the difference between the 13" rails offered by Geissele? This is for a custom build. The descriptions on their site are very vague and can't find a post that covers this. There is a lot mentioned about weight reduction and cheaper substitutions for the MK1, but at the expense of what? Cheaper materials? Strength?
MK1 vs MK2 vs MK3 vs MK4 vs MK5?

How do you guys like these rails?
Do you prefer Keymod vs the tapped holes to add rail sections?
View Quote


I'll give you a short synopsis, but more details can be found in the Geissele SMR thread in the industry section, or googling for info in other AR forums with a Geissele SMR photo thread:

Basically, the Mk1 was a copy of the original HK416 rail, but altered for the AR15 platform. It featured a fairly narrow width, and used threaded inserts to add extra rails. Heaviest design, but super-duper strong.

Mk2 was a cheaper variant of the Mk1, where instead of the thread-in rail sections, the rails had machined slots and backers to hold the rail sections. This is cheaper to make and for the consumer, but they were wider than the Mk1

Mk3 is a blend of the Mk 1 and 2, it is narrower than the Mk2, but still uses backers like the Mk2.

Mk4 is similar to the Knight's URX 3.1 rail, where there are only short 3, 6, and 9 o'clock rails at the ends, and a full 12 o'clock rail. Newer variants are addding Keymod.

Mk5 I believe will be full keymod.

Mk6 will be a full quad rail if I remember.


Basically the various patterns have had revisions to them, reducing weight by adding an Aluminum barrel nut vs the original Steel nut. Also, the original ones had longitudinal cooling slots on the bottom, but later ones have pear shaped diagonal cuts which reduced weight but kept strength.

ADD on- Try the Mk3. I'm not onboard the Keymod kool-aid boat yet, but the Mk3 gives you rails for the stuff you need, if you want them. 3 extra rails gives you a chunk for a VFG, flashlight, and a sling mount. There are also direct-mounts being engineered so you don't need the rails but aren't keymod. I had a hard time giving my upper back to my buddy when I installed the Mk3 for him. Loved it!
4/21/2014 5:26:51 PM EDT
[#2]
Thanks! Awesome reply. This helps a lot. Any idea when the MK6 is to come out? Kinda just curious to see it
4/27/2014 5:54:54 PM EDT
[#3]
If i'm looking at the Mk4's, any preference to the keymod vs. non-keymod? Kind of have it narrowed down to this one so far.

Also, any idea when we can expect to see the MK6?
4/27/2014 5:57:13 PM EDT
[#4]
Quote History
Quoted:
Thanks! Awesome reply. This helps a lot. Any idea when the MK6 is to come out? Kinda just curious to see it
View Quote


Same here.  A full quad rail made by Geissele...  
4/28/2014 5:47:37 AM EDT
[#5]
I recently purchased an MK4 non-key mod.
... not a big fan of the cock and balls look of the key mod.

considering an MK1 for my other gun.  
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