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2/7/2016 10:54:59 AM EDT
I am considering buying a dpms g2 ap4. Would it be possible to turn down the barrel nut to work with a bcm kmr? If not, please explain why.
2/7/2016 11:29:57 AM EDT
[#1]
No.
2/7/2016 12:46:01 PM EDT
[#2]
Is it because there isn't enough material to do it?
2/7/2016 6:56:28 PM EDT
[#3]
OD on the BCM KMR barrel nut is 1.365".

OD on the recess required for the cross bolts to secure the KMR in the longitudinal axis is 1.072" on my one sample.  I don't know why I have an extra KMR barrel nut, but I do for some reason.

That's what you need to machine on a GII barrel nut, after taking the nut down to 1.365" OD.  That 1.072" will probably bite you in the rear when trying to make the KMR work on the GII.

I would need a GII in hand to see what was dimensionally possible for a solution.

It would be a sick set-up though.
2/7/2016 7:28:03 PM EDT
[#4]
The recess for the cross bolts was what I was worried about. I have a kmr nut to work off of, and I figure if I screw the factor nut up, I just toss it. Whatever rail I buy will come with its own.
2/7/2016 9:17:23 PM EDT
[#5]
The barrel shank on the g2 is too big where the kmr bolts need to be recessed. No way to reduce the diameter of the not that much.
2/7/2016 9:57:57 PM EDT
[#6]
So I can't do it with mine, and chances are good we won't see anyone else come out with a kmr nut? Because it's just not possible?
2/7/2016 10:11:21 PM EDT
[#7]
You would need to drill and tap a 1.365" OD cylinder-shaped barrel nut for the GII if that's even possible to make. I have no dims for the threads on the GII upper where the barrel nut attaches.

Then drill holes on the KMR that correspond to the holes on the new nut.

You would ditch the KMR cross bolts and special nuts that help it clamp up top, as they wouldn't be needed anymore.
2/7/2016 10:23:44 PM EDT
[#8]
Quote History
Quoted:
So I can't do it with mine, and chances are good we won't see anyone else come out with a kmr nut? Because it's just not possible?
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I just had a g2 nut off. I'd say the thru bolts would have to move an inch or better away from the upper reciever face to fit between the barrel and gas tube. So barrel profile will be important right at the barrel nut.
2/7/2016 10:33:14 PM EDT
[#9]
Does someone make a receiver block for the new upper, or how did you go about disassembly?

And chances are good I will jus be going with one of MI's offerings.
2/7/2016 10:57:44 PM EDT
[#10]
I asked V7 and they said the barrel but on the KMR is too small to adapt to a G2.
2/8/2016 12:27:02 PM EDT
[#11]
Quote History
Quoted:
Does someone make a receiver block for the new upper, or how did you go about disassembly?

And chances are good I will jus be going with one of MI's offerings.
View Quote


I just used a regular wheeler clamp on ar15 block. not perfect fit but as long as everything isn't super tight it works.
2/8/2016 2:32:22 PM EDT
[#12]
Quote History
Quoted:
Does someone make a receiver block for the new upper, or how did you go about disassembly?

And chances are good I will jus be going with one of MI's offerings.
View Quote



DPMS makes a block for the GII  upper:  Google search for: 231-300-114WB GII 308 Receiver CLAW
2/8/2016 6:09:22 PM EDT
[#13]
Quote History
Quoted:
Does someone make a receiver block for the new upper, or how did you go about disassembly?
View Quote


Real vise, DPMS barrel nut wrench, barrel blocks, torque wrench, and leather. Going to need them to get the flash suppressor/hider off anyway if it's on anything like the Recon AAC piece.
2/9/2016 3:14:30 PM EDT
[#14]
Quote History
Quoted:
Does someone make a receiver block for the new upper, or how did you go about disassembly?

And chances are good I will jus be going with one of MI's offerings.
View Quote


I would look real hard at the SLR forends.
2/9/2016 6:02:48 PM EDT
[#15]
Quote History
Quoted:


I would look real hard at the SLR forends.
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Quoted:
Quoted:
Does someone make a receiver block for the new upper, or how did you go about disassembly?

And chances are good I will jus be going with one of MI's offerings.


I would look real hard at the SLR forends.


I am considering both. Still not wild about just friction holding the MI rail in place. Are there any accuracy reports on the g2 models with the light weight, chrome lined barrel?
2/9/2016 8:03:36 PM EDT
[#16]

Quote History
Quoted:
I am considering both. Still not wild about just friction holding the MI rail in place. Are there any accuracy reports on the g2 models with the light weight, chrome lined barrel?
View Quote View All Quotes
View All Quotes
Quote History
Quoted:



Quoted:


Quoted:

Does someone make a receiver block for the new upper, or how did you go about disassembly?



And chances are good I will jus be going with one of MI's offerings.




I would look real hard at the SLR forends.




I am considering both. Still not wild about just friction holding the MI rail in place. Are there any accuracy reports on the g2 models with the light weight, chrome lined barrel?


Depends on what accurate means to you. I don't have too much trouble putting most all 20 rounds into a 3" Shoot n C @ 50 yards, from a rest using irons or a red dot with any ammo I've tried. That is Wolf steel case, various surplus ball (including 60's corrosive Czech) or PMC Bronze. This out of my GII MOE. That's plenty accurate for me.



FWIW.



 
2/9/2016 9:39:02 PM EDT
[#17]
A Geissele Reaction Rod works.
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