Armalite AR10 B-series barrel nut TPI?

[goinbroke]

Hi. I recently acquired an Armalite AR-10 B-series rifle from my brother and I'm looking to convert it back to OEM form. It currently has a JP VTAC free float tube and I want to change it to either a clamshell or Armalite free float forend. So here's my question(s):

It's my understanding (I may be wrong) that the A-10B series uppers came in two different versions. One had a 16 TPI barrel nut and the other had an 18 TPI barrel nut. Firstly, is this correct? Secondly, is there a way I can tell which version I have without removing the JP forend and test fitting a known TPI nut? Thirdly, Where can I get a replacement barrel nut and forend? I've looked over Armalite's website and they have a very limited selection, half of which is out of stock.

Here's the rifle for reference:

https://imgur.com/a/s7hoe

Edited December 3, 2017 by goinbroke
photo link formatting

[survivalshop]

 You may be confusing the DPMS/SR25 thread Pitch  16TPI of the Barrel Nut & Armalite's AR10 which is 18 TPI , below is a link to Raley's corner who was a top Armorer with Armalite  with all the spec's you want on the Armalites rifles . 

https://forum.308ar.com/topic/11450-technical-specs/

And by the way , that JP Hand Guard is one of the best on the market .

Edited December 3, 2017 by survivalshop

[jtallen83]

5 hours ago, goinbroke said:

I've looked over Armalite's website and they have a very limited selection, half of which is out of stock.

Put yourself on the email notification list for the items you want, they come back in stock fairly regular.

[shepp]

Welcome to the forum feel free to tell us about your self in the intro section 

[Sisco]

I have a “B” model with a clamshell forend might be interested in a trade of foreends. PM me.

[goinbroke]

survivalshop: Thank you so much! That post is incredible. So it appears the Armalite pattern rifles ONLY come in 18 TPI barrel nut patterns. That answers my original question.

How does the JP handguard compare to the stock Armalite free float tube? I'm aware there's about a $100 price difference. Besides the modular rail accessories that can be added to the JP tube, is there any other difference? I'm only really planning on having a bipod attached as this is a 20" bbl model and it's really designed (in my opinion) for long range use, and the Armalite version has a swivel stud attachment point for the bipod. The closer to the original configuration I run the gun in, the less work I'll have to do when it comes time to sell it in the future, and I like the appearance of the Armalite free float tube.

jtallen: Good to know, thank you!

shepp: Thanks. Will do.

sisco: I'm not necessarily looking to get rid of the JP tube. I'm more interested in having the stock handguard on hand (along with an A2 buttstock) to convert the rifle back to stock in several years when I'm ready to sell it. Unless of course I find a handguard I like better in the meantime. Because this rifle is going to be dedicated to long range, I'd prefer a free float design versus a clamshell design for now. I'm also interested in what the original configuration actually was for my specific rifle, but I'm going to make another post about that because I think it'll be too off topic to the original post.