Geissele MK8 Rail on SBR - Hottttttt

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[ARCHIVED THREAD] - Geissele MK8 Rail on SBR - Hottttttt

Posted: 7/5/2017 1:42:54 PM EDT

OK - I just built a new 10.5" SBR and went with the Geissele MK8 Rail. Looks and feels great.

HOWEVER...

Took it out to the range for the initial break-in and test functionality.

This mofo gets *hot*. After 20 rounds, it's tough to even hold the rail. I do have a Magpul MLOK stop at the bottom, but the left side is tough to hold due the heat coming off of it.

Are others experiencing a similar issue?

Other issue I have is gas blowback running suppressed - get gas in the face after heavy sustained fire. Need to probably change out the Geissele gas block for something adjustable.

Posted: 7/5/2017 1:45:01 PM EDT

[#1]

Oh, and image:

Posted: 7/5/2017 1:49:37 PM EDT

[#2]

I am looking at a build with the 9.5 MK8, is this a 9.5 or 10? how much gap do you have between the can and the rail?

Posted: 7/5/2017 1:53:36 PM EDT

[#3]

Quote History

Quoted:
I am looking at a build with the 9.5 MK8, is this a 9.5 or 10? how much gap do you have between the can and the rail?

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Not much. Running a AAC 7.62 can.

Attached File

Posted: 7/5/2017 1:56:13 PM EDT

[#4]

maybe try the magpul panels? i have them on my G mk8 rail i just set up a month or so ago. it still gets hot but its also 90+ degrees here all the time now too and i always wear gloves shooting rifles, just a habit i guess.

seems like my picatinny railed uppers do run cooler though. i think the extra distance out helps and using tango down scar panels offers more insulation.

the mlok/keymod rails are a real love/hate. love the reduced diameter/hate the increase in heat.

Posted: 7/5/2017 1:57:38 PM EDT

[#5]

I haven't done any fast shooting, but my KMR doesn't seem to get to hot.

I have the hard plastic rail covers FWIW, I don't know if that would make a difference.

ETA: I also have a heavy-ish SS Noveske barrel, that may have more to do with it.

Posted: 7/5/2017 1:59:45 PM EDT

[#6]

Quote History

Quoted:
maybe try the magpul panels? i have them on my G mk8 rail i just set up a month or so ago. it still gets hot but its also 90+ degrees here all the time now too and i always wear gloves shooting rifles, just a habit i guess.

seems like my picatinny railed uppers do run cooler though. i think the extra distance out helps and using tango down scar panels offers more insulation.

the mlok/keymod rails are a real love/hate. love the reduced diameter/hate the increase in heat.

View Quote

I do have those on there, just not on the angled MLOK sections. I suppose I can buy more and try it out.

Posted: 7/5/2017 2:00:31 PM EDT

[#7]

It looked like a nice build until i saw what appears to be a knick right above the qd socket on your rail... maybe you should buy from manufacturers who actually care about their products

.

It will get hot... all rails like that do. Mechanix gloves will be your friend. Well done rifle A+

Posted: 7/5/2017 2:04:20 PM EDT

[#8]

Its a shorty with a can. It happens.

Posted: 7/5/2017 2:05:49 PM EDT

[#9]

I've had the same issue with all of my slimline modular handguards. My Geisele and KAC rail included.

So I went back to quad rails with KAC or Tango Down panels and I can now hold onto the rifle after dumping 3 mags.

Posted: 7/5/2017 2:10:54 PM EDT

[#10]

Quote History

Quoted:
Its a shorty with a can. It happens.

View Quote

My point is this will happen unsuppressed too - irrelevant of a can.

Hearing everyone loud and clear - just my first slim-lined rail so did anticipate this. I may switch back to a VFG rather than a hand stop and also order some more Magpul MLOK rubber guards too.

Posted: 7/5/2017 2:14:40 PM EDT

[#11]

Quoted:

Quoted:
maybe try the magpul panels? i have them on my G mk8 rail i just set up a month or so ago. it still gets hot but its also 90+ degrees here all the time now too and i always wear gloves shooting rifles, just a habit i guess.

seems like my picatinny railed uppers do run cooler though. i think the extra distance out helps and using tango down scar panels offers more insulation.

the mlok/keymod rails are a real love/hate. love the reduced diameter/hate the increase in heat.

View Quote

I do have those on there, just not on the angled MLOK sections. I suppose I can buy more and try it out.

View Quote

ah, didnt recognize those as magpul. mine are the larger ones with texture.

Posted: 7/5/2017 2:18:51 PM EDT

[#12]

Quote History

Quoted:

My point is this will happen unsuppressed too - irrelevant of a can.

Hearing everyone loud and clear - just my first slim-lined rail so did anticipate this. I may switch back to a VFG rather than a hand stop and also order some more Magpul MLOK rubber guards too.

View Quote

Unless you do the "beer can" grip (which i wouldn't recommend) it is going to be too hot to shoot for any extended period of time with bare hands, regardless of whether you are using a can or not. They definitely get hotter than you think faster than you think.

Posted: 7/5/2017 4:54:15 PM EDT

[#13]

Quote History

Quoted:

Unless you do the "beer can" grip (which i wouldn't recommend) it is going to be too hot to shoot for any extended period of time with bare hands, regardless of whether you are using a can or not. They definitely get hotter than you think faster than you think.

View Quote

true of all the guchi slim rails that dont have full picatinny. its all fun and games until you shoot them much.

Posted: 7/5/2017 5:05:50 PM EDT

[#14]

I have a G Mk8 9.5 being shipped home (currently overseas) for a 10.3 barrel and I assumed that heat transfer to this type of rail would be a factor. However I will be equipping the rail with G10 M-Lok panels. They do not transfer heat like metal and will not melt or warp since they're a composite high pressure type fiberglass. Also G10 is my favorite grip to have on a knife, just can't resist it.

Posted: 7/5/2017 5:16:40 PM EDT

[#15]

Quote History

Quoted:

true of all the guchi slim rails that dont have full picatinny. its all fun and games until you shoot them much.

View Quote

Yup... i'm using an LMT SLK8 as my primary so i am well aware of how hot they get haha. Left the gloves at home once and after 3hrs of using a magwell grip, i went and bought a few more pairs to keep in my range bag, car, house, etc. Quad rails can get hot too now tho!!

Posted: 7/5/2017 5:24:42 PM EDT

[#16]

Quote History

Quoted:
true of all the guchi slim rails that dont have full picatinny. its all fun and games until you shoot them much.

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:

Unless you do the "beer can" grip (which i wouldn't recommend) it is going to be too hot to shoot for any extended period of time with bare hands, regardless of whether you are using a can or not. They definitely get hotter than you think faster than you think.

true of all the guchi slim rails that dont have full picatinny. its all fun and games until you shoot them much.

Meh

I just put like 200 rounds thru this in half an hour, no gloves, 93 degrees out.

Attached File

And that is slimmer and lighter than my G/ALG stuff. Probably gets hotter than them, too.

Posted: 7/5/2017 6:53:15 PM EDT

[#17]

The magpul M-Lok Type 2 rail cover is what you seek. I have an mk4 rail, and they are perfect. No issues with heat, they grip well, and look great. Very secure too, no worries about them popping off.

Posted: 7/5/2017 7:04:43 PM EDT

[#18]

Quote History

Quoted:

true of all the guchi slim rails that dont have full picatinny. its all fun and games until you shoot them much.

View Quote

During qual every year, my M4 with a KAC RAS gets so hot that I can no longer hold it with bare hands. Picatinny doesn't magically make shit not get hot. It may take slightly longer, but it still happens.

If you really want to stop worrying about the heat, OP, and don't want to deal with gloves, your best bet is picking up some McNett Camo Form and wrapping the handguard where your support hand rides a few times. It works pretty damn well.

Posted: 7/5/2017 7:08:09 PM EDT

[#19]

Quote History

Quoted:
The magpul M-Lok Type 2 rail cover is what you seek. I have an mk4 rail, and they are perfect. No issues with heat, they grip well, and look great. Very secure too, no worries about them popping off.

View Quote

If you go through some heavy enough courses of fire, small plastic KM/MLOK covers really only delay the inevitable when it comes to the heat. Gloves are the best, but some type of fabric insulator wrapped around the handguard is going to work better than some thin pieces of plastic.

Posted: 7/5/2017 8:54:17 PM EDT

[#20]

Quote History

Quoted:

Not much. Running a AAC 7.62 can. https://www.AR15.Com/media/mediaFiles/62333/image-246723.JPG

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Damn thats a sexy beast! Thanks for sharing, and good luck with the gloves, or whatever you do....

Posted: 7/6/2017 1:55:10 PM EDT

[#21]

Heavy barrel + quad rail + tango down panels = mag dump machine.

Posted: 7/6/2017 8:00:31 PM EDT

[#22]

What I was shooting earlier this week, me and the wife. A mk8 with colt socom, NSR with SS noveske 13.7 and her original KMR 14.5 and 10.5. We got all of them so hot you couldn't hold the rail, the single shield plastic were worst probably, I'm betting they were close to melting at one point. The mk8 is better than the NSR and KMR, probably because it's a little farther away from the barrel and has a little more mass. The NSR with rail covers I got pretty damn hot too, too hot to hold the rail for more than a few seconds. I think it's maybe a little better than the KMR, but hard to say. Overall I think the mk8 does pretty good, considering I ran that socom the hardest and could still somewhat grip the rail without burning myself.

Posted: 7/7/2017 3:23:07 PM EDT

[#23]

Quote History

Quoted:
During qual every year, my M4 with a KAC RAS gets so hot that I can no longer hold it with bare hands. Picatinny doesn't magically make shit not get hot. It may take slightly longer, but it still happens.

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:

true of all the guchi slim rails that dont have full picatinny. its all fun and games until you shoot them much.

During qual every year, my M4 with a KAC RAS gets so hot that I can no longer hold it with bare hands. Picatinny doesn't magically make shit not get hot. It may take slightly longer, but it still happens.

really? i woulda never guessed...

good shooting gloves are were its at or atleast some thin mechanix like the thin 0.5mm ones.

[ARCHIVED THREAD] - Geissele MK8 Rail on SBR - Hottttttt

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