Regarding the POF handguards with the heat sink barrel nut, is there any reason not to use diamond thermal compound on those surfaces?

What I mean is applying the thermal compound on the threads before installing the barrel nut (the part with the heat sink). I'm a little surprised I'm the first person to bring this up. I mean, how is installing a heat sink on a gun any different than installing one on a CPU? And you wouldn't skip the thermal compound on your CPU, so why do it with your gun?

I guess my main question is, am I missing something? Will it hurt the gun in any way?

Thermal grease breaks down over time, I wouldn't use it on any firearm.

Even the 90% diamond paste? I'm talking the super high grade stuff. The company claims that's exactly what it doesn't do...

well, do it, write it up, and show everyone the new way after a lot of testing.

Yea, I'm hoping to hear from someone who's already done it, just to make sure nothing disastrous happened. I'm still waiting to hear back from POF.

Thermal paste is not even in the ballpark of the correct barrel nut lube.
There is likely a reason you are the first to bring it up.
However having never heard of or doing that I can’t say it will cause damage.
Worst case uppers and barrel nuts are not that exspensive.

Okay, POF got back to me. They said it has no effect. Back to the drawing board...

Thermal grease is a silicone grease with zinc oxide and sometimes a little bit of other stuff.  The base grease isn't going to do much good if there isn't an active system to move heat through it.  Take a look at any PC whose CPU fried because the fan died - the heat sink compound winds up cooking before the chip dies.

Not needed.

Vince

IAW military practice the weapon isn't supposed to be heated to the point it would be needed. That goes to the tactical use of it as a self loading rifle, not a machine gun. The M-series simply doesn't have the mass or build to fire full auto for extended periods of time. The sustained rate of fire - what you do for extended periods of combat - is 12 to 15 rounds per minute. At that rate it cools quickly enough to pass off the excess heat.

Note carefully that even on the unit machine guns - M249, M60, M2 .50 - heat dissipating paste isn't required or even wanted.

As a further note, when Colt tested their barrels for heat resistance, the area near the M203 cut and gas block were the main cause of failure after 750+ rounds of continuous full auto fire. Not the barrel nut. The average soldier only carries up to 450 rounds maximum, usually less, and firing it full auto would only cause him to run out of ammo quicker - not defeat the enemy by accurate fire. He would quickly become a weak link in the line and be a failure point in battle.

All that to back up why 90% diamond paste is overthinking it.

I hear ya. But there are other reasons to try to draw heat away from the chamber. I realize that the AR will most likely never reach its failure point in most engagements. On the other hand, I have heard isolated incidents of ARs failing in a firefight due to overheating. Most of those complaints seem to come from SOF, which I suppose would make sense. There was also an incident where these guys were pinned down inside a walled village for over 24 hours. They kept getting ammo dropped in by air, and they were really pushing all of their weapons to the breaking point. Anything that helps cool the gun will increase the safe RPM range, which could come in handy if things got bad.

More than anything though, keeping the gun cooler just helps it operate better. It increases the barrel life, it improves accuracy, and it increases reliability.

I think that POF and JP are on the right track. I'm starting to think that all automatic guns should have a heat sink. It only adds a few ounces and seems to make a pretty big difference. I would really like to see more companies using heat sinking barrel nuts on their handguards.

Like I said, back to the drawing board.

I just shmear Aeroshell 33ms on the threads also never had a problem so I won't be straying from what I normally do.