want to build a dissapator need info

[Magwa]

got me a really sweet billet lower Franklin arms the workmanship is simply stunning I want to build a 16 inch dissapator with rifle lenght gas system... anyone have any tips I want to use the A2 front sight and it will be a iron sight gun.. Thanks

[blue109]

I have 2 built on DTI barrels. Run perfect. They are only 1/9 and not chrome but I only shoot 193 through most of my rifles so no biggie for me.

[Robocop1051]

Make it a woody too! A Dissapator/Woody would be nice.

Model1 sells Dissy barrels. Lots of options there. Traditionally the barrels were carbine gas, but Mod1 sells 16" mid length dissy barrels.

If you want to use an actual rifle length gas, I suggest making it into a piston gun. Otherwise you'll be stuck using heavyweight projo's all the time.

If you decide to build from scratch, and you don't buy a Dissy barrel, you have to get creative. I built a 14.5" 300Blk and made it into a Dissy. I suggest the YHM side clamp lo-pro gas block. Then the Armalite clamp on A2 sight.

If you like the A2, and you think you'll ever mount s scope, check out the flip-up A2.

I have a two Colt A2 uppers, a 16" HBAR and a 20" HBAR. I plan on a woody/Dissy for at least one of them.

[Magwa]

I have 2 built on DTI barrels. Run perfect. They are only 1/9 and not chrome but I only shoot 193 through most of my rifles so no biggie for me.

yours are rifle lenght or mid lenght gas systems?

[blue109]

Rifle length. I know the internet says it can't work and dwell time and buffer weight and blah blah. I have 2 basic built rifle length dissys that run perfect on 55gr federal. I've only put a few hundred through them and desert shooting so no accuracy data yet...but they work.

I thought the original dissys were chopped down 20" guns?

[Robocop1051]

Blue, did you widen the gas hole?

[blue109]

Nope. From what I read the DTI Barrels have a bigger gas port but I don't have any cool tools to confirm that. I bought one complete barrel from del tons website for about $160. Second came from jse stripped for $105. Certainly not high end...but they work.

[Magwa]

Pictures please.... :)

[Robocop1051]

14.5" 300Blk w/ Carbine gas.

Modified PRI (faux) gasblock, BABC, Magpul MBUS

[Rsquared]

Oh my god! What happened to your mag? Did you break it over someones head while doing a linebacker tackle on them or...................................Oh....that's right...........Cali. <laughs>

Nice lookin rifle though.

 

Don't feel too bad brother. My state is going to the 10 rounders also.................RAT-BASTARDS!

Edited May 17, 2013 by Rsquared

[98Z5V]

Mike, the most trouble-free way to build this isn't with a rifle gas system.   Just use a 16" carbine gas system, and you'll have the most freedom in the build, and it'll operate with the widest ranges of ammo, and you cam run a faster twist rate of 1:7, for the heavy bullets. 

 

Now, keep in mind that twist and bullet weight isn't the correct way - it's just what we do, and recommend.  The real deal is twist, and bullet length.   Since we're constrained to a diameter (.224" on the 5.56 guns), when you go heavier on the bullet, it has to be longer (all comstruction principles being the same (i.e., copper jacketed lead core, etc.)

 

I offer this to you, my brother - I know you love some .308 Win Barnes TSX.  IF Barnes ever brings back the .224" TSX, or TTSX, those are some LONG projectiles.  Longer than something of similar weight, that is constructed of a lead core, copper jacket.  You'll need a 1:7 twist to run some 62gr or 69gr 5.56 TSX rounds.

 

Okay, with that out of the way, I recommend the 16" carbine gas.  You have freedom to build it how you want, the barrels are more readily available than anything else on the market, it's at or over 16" so you don't have to legally pin the comp or flash hider onto it to get it legal, and you don't have to do any custom machining.  Rob's 14.5" dissy has custom machining.  If you truly want to run a front sight base, it's not gonna fit on a 14.5" barrel 1) unless that barrel already has rifle gas, or 2) without some custom machining.

 

Carbine gas is reliable with almost every type/weight of ammo out there.  You can depend on it.  If you feel the recoil is harsh (it's not bad, at all, in reality), then you just toss in a H2 or H3 buffer.  Done. 

 

16" carbine gas barrels are everywhere - maybe not right now, but...  Seems everybody wants an M4 lookalike, and they need it legal.  Carbine gas, and 16 inches.  Every company that makes barrels, makes a 16" Carbine barrel. 

 

I've got two "Dissy" rifles - even though one is kinda cheating.  My 45AR is blowback operated, so it doesn't even have a gas system, at all.  It's still a 16" barrel with rifle-length handguard, and a fixed front sight base - the same Armalite clamp-on A2 base I talked you into...  <thumbsup>

 

My 300BLK, though not finished yet, will be a Dissipator - 16" barrel, running carbine gas.

[blue109]

I love that rifle robo.

[edgecrusher]

I just bought three boxes of Barnes 62 gr TSX projectiles, they are out there

[98Z5V]

The 45:

 

 

The cheat - no gas system...

 

 

 

The Blackout barrel configuration is below vvv...

 

 

[98Z5V]

I just bought three boxes of Barnes 62 gr TSX projectiles, they are out there

They're long bastards, because of the gas checks they build into them, and because of the solid construction...  They need a fast twist.  <thumbsup>

 

The 70 TSX I load up - some of those are longer than some 75 and 77gr projos out there.  I'm damn near out of those things, and don't dare shoot what's already loaded.

[EasyEJL]

The 45:

 

 

 

 

 

 

threadjack... I got on a list for blemished CAV15s for $110 since they take the grease gun mags :) can you point me to where I can find a .45acp bolt and/or full carrier + barrel?

[Robocop1051]

Oh my god! What happened to your mag? Did you break it over someones head while doing a linebacker tackle on them

Lol. That's my custom 5 round "stubby" made by MidwestPX. We can only hunt with 5 rounds in our rifles. I built my 300Blk to hunt pigs.

[Magwa]

Brother Tom I always love your advice, and most times I take it I love the armalite front site gas block and could run it and not use it as a gas block but use a small gass block under the handgaurds now my last question before I start chasing parts would a mid lenght gas system work?

 

  PS. I just bought 2 boxes of barnes ttsx 55 and both of my 5.56 guns are 1in 7 twist my A2 loves 55 grain bullets and is sub MOA with them. I am stoked to get this prodject going might see another Apex rifle lenghts flree float on the horizon/..... and I have no problems with any of the recoil on 5.56  I am used to shooting a 7mmSTW anything else is gravy.....

[Matt.Cross]

Brother Tom I always love your advice, and most times I take it. I love the armalite front site gas block and could run it and not use it as a gas block, but use a small gas block under the handguard. Now, my last question before I start chasing parts, would a mid length gas system work?

 

  PS. I just bought 2 boxes of barnes ttsx 55 and both of my 5.56 guns are 1 in 7 twist. My A2 loves 55 grain bullets and is sub MOA with them. I am stoked to get this project going, might see another Apex rifle length free float on the horizon..... and I have no problems with any of the recoil on 5.56.  I am used to shooting a 7mm BTW, anything else is gravy.....

 

Fixed it for you bro.  <thumbsup>

[98Z5V]

Brother Tom I always love your advice, and most times I take it I love the armalite front site gas block and could run it and not use it as a gas block but use a small gas block under the handgaurds now my last question before I start chasing parts would a mid lenght gas system work?

 

 

Well, midlength gas on a 16" will give you about the same dimension as running carbine gas on a 14.5" - it's all math, and how much barrel (forward of the gas port) that you have to work with, when getting a Dissy together.. 

 

7" carbine gas system on a 14.5" will give you roughly 7.5" working length to make a Dissy - and that's tough to do.

9" midlength gas system on a 16" will give you 7" of barrel to work with - gonna be tough to buy off-the-shelf parts and get a Dissy together, brother.

 

Not impossible, but you're back to the "machining" side of the house again, running midlength gas.  <thumbsup>

[edgecrusher]

Addax seldom a dissy barrel that I look at, trying to hold out, maybe we can get a tester?

 

Nevermind, they don't even list it right now, but maybe it'll come back.

Edited May 18, 2013 by edgecrusher

[edgecrusher]

Sells not seldom, stupid auto spell!

[98Z5V]

threadjack... I got on a list for blemished CAV15s for $110 since they take the grease gun mags :) can you point me to where I can find a .45acp bolt and/or full carrier + barrel?

Honestly, start looking for the whole upper.  I hit the Oly upper with one mag, and got it from Rainier Arms.  Piecing them together is TOUGH to do when things are good, let alone right now with tings still stupid.

 

Nail the GG mags through KeepShooting.com. 30-rounders, new production. 

[Robocop1051]

I use this YHM side clamp gas block. It fits under everything I've tried so far.

[98Z5V]

The DD Mk12 gas block is also very small, and YHM makes another very small one like that, but with set screw attachment.  They'll also both fit under everything I've got, including the DD Mk18 RIS II rail - that's the smallest inner-diameter rail I have.