I think I could build my own float tube sleeve. I have a tig welder and a milling  machine, I want to make it as light weight as possible... My question is how much of a problem would welding a barrel nut be meaning weakening the metal and possibly blowing myself to kingdom come..... I could build if for like 15 bucks on my own wtf right lol

There would be no welding to the barrel, that would defeat the purpose of making a free float tube. It would only be welded on the nut and had guard cap to a thin a walled tube . I plan to use standard hand guards over it. I am planning to make sleeve if you will like the National match ones armalite and RRA sell only a lot lighter weight.. I will be using a KAC m5ras on the tube. I do not have a lathe to make a proprietary barrle nut so I will have to use a standard one (7 bucks). Is there any risk of weakening the barrel nut that would allow the gun to have issues. Basically I'd be ruining a barrel nut, and hand guard cap.

Edited changed but to nut....

Why would make a float tube require welding to your barrel? Never seen that done.

Barrel nut autocorrect changed it to but....

I have to ask the same thing, why would you need a welder? If you have a mill, and actually know how to use it, a piece of extruded aluminum tube and a design should be all that's needed. That said, there are a plethora of options on the market at low cost, why do you want to make your own? Nothing you like at the price, or just cause?

There would be no welding to the barrel, that would defeat the purpose of making a free float tube. It would only be welded on the nut and had guard cap. I plan to use standard hand guards over it. I am planning to make sleeve if you will like the National match ones armalite and RRA sell only a lot lighter weight.. I will be using a KAC m5ras on the tube. I do not have a lathe to make a proprietary barrle nut so I will have to use a standard one (7 bucks). Is there any risk of weaking the barrel nut that would allow the gun to have issues. Basically I'd be ruining a barrel nut, and hand guard cap.

I think you're reinventing the wheel. I don't understand how you can make a NM type float tube any lighter than it already is unless you use different materials such as aluminum and that won't allow it to use standard hand guards (Or the drop in KAC version). Maybe you could machine away some material to remove weight?

Go Here an read about installing an Armalite NM tube. Then come back and tell us how you intend to improve upon it by making it lighter. If you have a new idea that hasn't been thought of before I'd like to hear it.

You do understand that the barrel nut doesn't contain the pressure of firing, right? Weakening the barrel nut would only allow your barrel to become loose, not the rifle to explode.

You can make a barrel nut from aluminum without safety issues, some free floats do just that.  If you do a good job of welding, you should be able to keep the threads and clamping surface from overheating....

You nay-sayers are acting like its possible to just go out and buy what he wants.  He wants a free-floating, quad-railed hand guard.  What other choice does he have but to bust out the TIG welder and re-engineer competition equipment meant for a very narrow purpose?

Idk If there is such thing, but I'm putting you in for arfcom mothafucker of the year award for your outstanding content.

Since my RIS II doesn't meet any of that criteria at all, along with 80 percent of rails on the market, I must suggest a +1 to tig welding up his own, especially considering the weldability of 6061 and 7075 aluminum is poor at best. Sounds like a great option.

Well, off the top of my head -  you can cut the clearance slot for the tube after installation....there are probably other ways too....

6061 welds very well.

7075 does not weld very well.

It didn't for me. I'm mainly a GMAW, FCAW, SMAW welder, but the one time I GTAW'd 6061 let's just say my puddle wasn't happy. perameters were spot on for where they shouldve been as well. I've never been all that great at GTAW anyways though.

ETA on aluminum anyways. I can GTAW like nobodys business on mild steel w/ 2 percent thoriated tungsten, but aluminum and I are sworn  enemies so I mainly stick to mild steel.

If you are building an upper to compete under service rifle rules - they do allow quad rails now like the Larue 12.0

Topic Moved

my thoughts as well....Titanium Barrel Nut.....Titanium fasteners.....Aluminum or Carbon Fiber or do what BCM has done with a blend of Magnesium & Aluminum....

You could take a KMR and mill off the upper rail and go with a V7 Ti barrel nut and their Ti mounting hardware (they still need to bring out some more
Ti hardware for it but they're almost there.