RS DPMS Free Float Tube Handguard and G&P Reciever

[Chiba]

I recently purchased a DMPS 7" Free Float Tube (Handguard) and was installing it on my G&P M4 (AEG) Reciever yesterday.

However, the Free Float Tube only screwed on halfway before it wouldn't turn anymore. I tried adding lubrication on the threads but no dice.

Should I assume this is a threading issue? I thought that G&P used imperial threading, which is compatible with real steel stuff.

Has anyone have had experience and would like to help out?

Thanks!

[Stealth]

Nope. G&P threads are NOT real steel threads.
I had a Troy VTAC rail and it didn't go on without modifying the threads.

[L473ncy]

Actually I also thought it used imperial threading. That's why Madbull had to make a special Barrel nut for the Noveske rail and DD rails for the G&P....

@ Stealth: Can you tell me why G&P threading different from most airsoft "standard" threadings in such a way that I need special barrel nuts and special delta ring assy's. as well?

@ Chiba: For some reason I was able to thread a real steel bushmaster free float handguard on a Madbull upper, I don't know why or how but it fit and threaded in properly.... So yeah.... Take from that what you will...

[Chiba]

Originally Posted by Stealth

Nope. G&P threads are NOT real steel threads.
I had a Troy VTAC rail and it didn't go on without modifying the threads.

What? But most searches online (including on this forum) indicated its Imperial. Crap.

So based on this I should do two things?

1) sand off all the paint on the thread and try to fit?
2) if that doesn't work start thinning the threads while maintaining pitch? if I have a dremel.. what's the best way to do it?

Crap~

[L473ncy]

Actually I just remembered. Madbull has these Delta Ring modification kits that "resize" the threads. I have no clue how it works but appears to be a hard material that rethreads the delta ring threads on your airsoft upper.

http://madbull.com/catalog/index.php...roducts_id=103

[Stealth]

Originally Posted by L473ncy

@ Stealth: Can you tell me why G&P threading different from most airsoft "standard" threadings in such a way that I need special barrel nuts and special delta ring assy's. as well?

Honestly I wish I could give you a quantitative answer but I don't have a thread measuring tool. All I know is that G&P receivers (circa 2011/2012) are neither standard AEG thread nor real steel thread.

I've had good success with a triangle file but you need to be quite careful. I've also used the Madbull rethreading tool with some success. It depends on how far "off" the threads are. Also, because of the hardness of the die, it can be quite brittle.

[Chiba]

I went to a tech today and they also confirmed the G&P threads don't work with real steel.

for 15$US (eqiv.) for rethreading work, I think I'll just let them do it.

But I also heard on other forums to just brush off as much paint as possible off the threads for it too work.

Geez they've gotta standardize these things hahaha.