Possible to turn carbine length upper into dissipator upper?

[KevinXT]

Ive found a killer deal on a carbine length upper and was wondering how hard it was / if possible to turn it into a dissipator style upper ( rifle length sights but keeping the carbine length gas system. Would a normal low profile gas block fit under the hand guards? and any issues with re pinning the A2 gas block farther up on the barrel?

[Josh3239]

Yes it can be done. Either shave down the original FSB or trade it for a low profile gas block. Then you need the appropriate length handguards and the new or original FSB depending on what you did in the first place. Depending on your barrel, I think there could be an issue with pinning it, but you could always get a clamp on or set screw style FSB or modify a regular one to a clamp style.

[Bug Splat]

Don't think you could pin a new gas block up there. The barrel will be smaller diameter then where the gas block should be mounted to. You could try a clamp but I don't think it will hold very well. Maybe with shims it might. It think you are asking for more trouble than its worth. I think you are better off selling the barrel, and getting a new one and a new gas tube. Standard handguards are cheap too.

[stevie]

What kind of carbine upper you got? I have an A2 bushmaster Dissy that i had ADCO slim down the BBL and thread for flashhider... Round count under 1000 if interested in trading....

[KevinXT]

i dont have one yet... was considering buying it...

looks to me like a dissipator uses the same profile barrel as a carbine m4

[stevie]

The dissy is usually a carbine gas system with a full length (rifle) A2 front sight attached.

If you use a 16 inch M4 type BBL with front sight. You will need to shave down the existing front sight to fit under new handguard. Then put on a new front sight.

It would be easlier to just buy a dissy instead of modifying a new M4 style.

[Artery]

This would be a really backasswards way to do it, but if for some reason you couldn't get the "second" FSB onto the barrel because of the profile you could mount a full length omega rail and then mount a buis up front.

[mltrading]

Why dissipator? Just for the look and longer sight radius?

Since the works are related to the original FSB, how about chopping the original FSB then install a rifle-length free-float forearm? Then put on a detachable front sight on the forearm to make it look-like-A2.

[Eastbayguy]

Pity, that you are not local, I just posted:

http://www.calguns.net/calgunforum/showthread.php?p=3533414#post3533414

[dfletcher]

i dont have one yet... was considering buying it...

looks to me like a dissipator uses the same profile barrel as a carbine m4

That's how mine looked. Plain old M4 barrel with a lp gasblock. The FS is for sights only and does no gas work at all. So long as you get the FS on straight & snug against the guards you're fine.

[pacrimguru]

i have a dissipator upper and didn't even know that's what it is called. i kept calling it "carbine gas system with rifle length sights"... you learn something everyday on calguns.

[KevinXT]

That's how mine looked. Plain old M4 barrel with a lp gasblock. The FS is for sights only and does no gas work at all. So long as you get the FS on straight & snug against the guards you're fine.

the question is how do you get it straight ... just eye ball it?


i was planning on running a A2 stock and like the look of the dissipator... basically full rifle look and feel with the quicker handling of a 16" barrel..
but i suppose a full rail could acomplish this but cost alot more and i was planning on keeping things simple... im a keep it simple kind of guy...

[CrazyJeep]

I just finished building mine. I've wanted one for the longest time. Finally gathered the funds to build it.

[pacrimguru]

off topic, but anyone know why this style upper is called "dissipator"? what is it dissipating?

[KevinXT]

off topic, but anyone know why this style upper is called "dissipator"? what is it dissipating?

heat dissipation