Going to build a Dissipator

I have tried to wait for BCM to offer a Dissipator. But I have decided to build one using an Adco barrel assembly. This rifle will be my “irons” rifle used for carbine/3-gun matches. It will also be my KISS rifle. Any suggestions on this?

Adco quoted me $450 for the dissy barrel set-up . This seems a little pricey to me since whole uppers can be had for around this amount. But I am not seeing any other “quality” barrel assemblies. I definately want a pinned FSB and GB with mid-length gas. Heres a breakdown:

Adco CL mid-length barrel - $225
Barrel nut and end cap assy $10
Pinned gas block - $75
FSB Install $130
Gas tube w/assy $10

FWIW PSA does offer a dissipator style upper and complete gun if you’re not specifically wanting ADCO

I appreciate the suggestion. I actually purchased one of those several months ago. I returned it because the barrel diameter was .735" under the FSB instead of .749-.750" like it should be. This made the FSB a little bit unstable.

Addax Tactical sells a complete upper, but as with most of their stuff, it’s a bit pricey.
http://www.addaxtactical.com/store/pc/ADDAX-MK2-ELITE-DISSIPATOR-5-56-RIFLE-LENGTH-16-UPPER-RECEIVER-ASSEMBLY-VLTOR-MUR-PWS-ENHANCED-BOLT-CARRIER-1-8-TWIST-POLYGONAL-3-R-BARREL-166p5887.htm

Wow, that makes me feel better. I figure that I will have $700 in the Adco upper by the time I add the upper reciever and make it complete.

That Addax upper is a 16" with a rifle gas… I thought that caused issues due to the ports being so close to the muzzle.

ZombieKiller did a pretty good dissy build using a JP bolt on FSB.
https://www.m4carbine.net/showpost.php?p=1004195&postcount=369
using this part:
http://www.bravocompanyusa.com/JP-Adjustable-Gas-Block-Front-Sight-Base-p/jpgs-2fs.htm

If your willing to go used troll the classifieds for a while you should be able to find a 16" BCM carbine upper with all the hand guard furniture. Add a lo pro gas block and the JP FSB and your GTG. Might not be quite as rough and tumble ready as a pinned FSB, but close.
This might be a good candidate, and you’d recoup about 100-150 selling the RIS, but its not BFH:
https://www.m4carbine.net/showthread.php?t=116855
And there are plenty more 16" Colt, DD and BCM uppers still for sale.
Allen

As much as Spikes Tactical is despised on this forum (rightfully so), I would consider this for a Dissy build until BCM decides to crank them out. Spikes builds this upper specifically for AIM surplus. I have yet to see this Dissy build on any other site. $579.00 complete upper w/ BCG, charging handle, and MOE rifle handguard.

http://www.aimsurplus.com/product.aspx?item=XSTU5950MOE&name=Spikes+Tactical+16%22+Mid-Length+GMP+5.56%2f.223+Upper&groupid=586

Thanks fellas. Thats a pretty good price on the Spikes Dissy. But I guess an extra $100 or so will insure a top notch upper. I have heard such great things about work done at Adco.

Have the front of your favorite 16" barrel turned down to .625" and a .625" front sight installed.

I’ve been on the notification list for that upper for almost a year and i have NEVER seen it come back in stock. I even contacted spikes to see if they’re still making it. They confirmed that they still are but they can’t disclose information on when aimsurplus will have more in stock.

This is what ADCO did on my Noveske 16 inch intermediate length bbl

Got it set up with a VLTOR MUR 1A and a PRI rifle length tube.

It’s a Defensive Edge “Sully” clone.

Well… I’m holding out for a BCM… Hopefully they get on that this winter at least.

That is likely the next upper that ill buy.
So why again is Spike’s so despised?

I hate that their carrier and upper are branded in an unavoidable way. To me the brand is less than stellar but it reminds you what it is everywhere you look. Some people suggest the logo looks like two dicks touching.

It’s mostly the branding I don’t like. If BCM did one with their (better) branding and a LW CHF barrel, I’d be all over it. For the spikes, there isn’t really any telling what you’re getting for a barrel.

How is this possible with the FSB pinned?

Its possible because they just placed the FSB onto the undersized barrel into the drilling/reaming fixture, then drill and ream for the pins. The drive the pins in. The pins make the FSB seem tight, but since it doesn’t contact the barrel all the way around, its not as solid as it should be.

I just noticed that PSA has Dissipator uppers instock again. But I am afraid to take a chance on them again. I will pay the extra $100 and know that its right with ADCO(gas block will be pinned too).

Has anyone used the Adco barrel? This is a 16" Mid length gas system, 1:7 twist, chrome lined, mil-spec MIL-B-11595E CM-V steel with a 5.56 chamber. http://www.adcofirearms.com/itemdetails_.cfm?inventorynumber=5202

I am hoping for 1MOA accuracy out this with XM193 ammo. Is this asking for too much? My alternative is to turn down my Troy barrel down to .625 like suggested above and have Adco pin the FSB.

Yes. Expecting MOA with cheap ball ammo is asking too much.

Can’t blame a man for hoping. My non-CL RRA may have spoiled me.

I bought a chf dissy from PSA last year. I quickly realized that the useless fsb hanging off the end of the barrel was heavy and I could achieve the same sight radius using a ff tube and a detachable front sight. So, I added a DD MFR and a DD front sight. I feel as though the gun balances much better now and I would argue that is lighter but I didn’t weigh them before and after. Just my .02