Misc Posts on Barrel Heat reduction
It works. I got an increase in accuracy after using it. But the greatest and most noticable effect was that the barrel didn't heat up as much after about twice as mch shooting as befoe. I'll keep using it.
Volquartsen & MolyFusion
Quite a while back, I did a little experiment. I shot and cleaned my VQ .17HMR close to the breakin process. (Clean, shoot a few rounds, clean and shoot a few more) Did this for 50 rounds.
Then I would start with a cold barrel and shoot 5. Groups were good but as barrel got warm groups never got better. Barrel would be cold at muzzle and hot at chamber.
I decided to do a good MolyFusion treatment by the book. Went out and shot again and noticed that the barrel seemed to get warm more "Uniform" from chamber to Muzzle. ??? ?? It seemed to be warming up same from one end to other.
Decided to go nuts and see what happened. "Shot 4 full Magazines thru it as fast as I could, Barrel was hot as hell from one end to the other". THEN I shot a 5 shot group to see what the high temp did to accuracy. "WOW" The groups were the tightest I had consistantly shot WHY??? Only thing I can figure is the temp of the barrel was the same from one end to the other.
Why is uniform temperature above a good thing?
Cold barrel harmonics differ from hot barrel harmonics. A warm throat and cold muzzle is going to be another thing all together.
Like anything else, once the entire thing is uniform, the harmonics should be the same shot after shot.
I am sure there are other potential reasons, but as we all know, harmonics plays a huge role with rimfires.
Jonathan Doege responds:
I think a uniform and stable temperature throughout is good.
It helps achieve this be reflecting heat, preventing the barrel from getting nearly as warm as it would.
Combine this with your measured 100 fps increase, and this should help explain why the barrel warms up at the muzzle now and at the same rate as the rest.
Combined in the equation is a thick barrel, which helps distribute the heat evenly.
With heat reflectivity, the powder itself will be burning later in the barrel then normal, even though friction is eliminated. This would overcome reduction in peak pressure if heat reflectivity was pronounced enough, and net a velocity increase.
Eliminating friction alone cannot explain what is happening: velocity would be reduced if it was that simple.
There is no metal build-up in the bore, so everything keeps working. Moly-Fusion = Molybdenum-Fusion.
Molybdenum is a refractory metal noted for its heat refelectivity properties. It glows purplish, according the the US Patent office who both stated it reflects heat and the combined process eliminated severe sizing up to 300,000 pounds per square inch, and then wear was a fraction of what it was at near zero pounds per square inch.
Moly-Fusion continues its enhancement, but it does more then one thing.
The fact it is the steel and not built-up is a positive factor.
Bill [Redtip17], I asked you a question in benchrest you are explaining some of it here - except for the velocity increase. The velocity increase and the now warm muzzle means the hot gas is expelled hotter then normal, causing the uniform temperature condition.
Instead of Heat Reflectivity it means Radiated Heat stopped from instantaneously being absorbed into the surface. In other words Heat Reflectivity could be stated Heat Refractivity as a synonym.
Shamus same thread
So your saying a mitten for my muzzle is a good thing
I've still not run 500 rounds through my barrel and for that reason have held off with any Moly treatment. That and I am still trying to grasp what is happening to a round when I pull the trigger.
I'm not just talking about a barrel lube. I'm looking at bedding, harmonics, barrel crown, length, ambient temperature and the list goes on. Obviously there are a bunch of factors playing upon a fired round and no doubt you could take this to an extreme. What I need to know is what issues I can easily address every time I visit the range to be as consistent as possible. (Lets forget the "me" factor for now)
Bill, your particular set-up is certainly nothing similar to my VQ factory with Hogue stock. Is your barrel free floated and/or do you use a pad under the end of the barrel?
As for moly, how often should a barrel be treated? (Number of rounds fired)
Can you remove moly from a barrel and if so how?
What product should I use to clean my barrel and how often? How does a cleaner effect the Moly?
I should live in Missouri...
Followup (same thread) to Shamus that followed up Jonathan Doege's Post (Techshooter)
I bedded the action and the first inch in front of the mounting lug only, the rest full floats enough to run 2 business cards under it.
As for MolyFusion treatment : The Volquartsen bore is so smooth (1-5 Micro Finish) and uniform in diameter that there is basically no breakin needed.
MolyFusion treating a VQ bore is not when you do it BUT if you do it. I did mine early on and noticed that it picked up a little velocity uniformity AND ease of cleaning. I think I ran only 100 rounds thru it before treating it. I've run probably 5 bricks thru it and only retreated it after the first 1000 rounds.
It is just as accurate now as it was after the first 1200 rounds. I will retreat it after 5000 rounds.
It won't hurt anything to do it except improve the life of bore and reduce wear and fouling to almost nothing.
MolyFusion basically cannot be removed because it is NOT A COATING but becomes chemically bonded with the steel molecules making a heat reflective and much more friction free surface. Cleaning is a snap with a treated barrel. Bill
PS: I've treated every gun I own. ESPECIALLY the Ol' Black Powder ones. Made cleaning a real easy job. As you can tell I'm sold on it. In fact I even did my RWS airgun barrel and gained 80-90 fps velocity.
Technical research by luvtolean, ME: (Same thread, pondering the ME Science behind the reported results.)
...Molybdenum has a very high melting point, 2894K (4750ºF) so from that persepective it could be used as a refractory metal...
I can assure you ... about the thermal conductivity. This is an easily checked material property. Most books use "k" to symbolize thermal conductivity, and the metric units are W(atts)/ [m(eter) * K(elvin)]
From my heat transfer book here are a couple of k values (at 300K (80.3ºF)) to ponder (higher conducts more heat):
molybdenum: 138 (W/m-K)
plain carbon steel: 60.1 (W/m-K)
AISI Stainless 302: 15.1 (W/m-K)
Now of course, this doesn't argue against moly-fusion in any way, it just helps explain why it works. If someone wants to spend $25 bucks on it and is happy, I have no problem with that. But this exercise is forcing me to think about what happens to a gun barrel during firing, which is pretty fun. You may all think I'm overanalyzing, but I do this kinda stuff for a living, so it's how I think. And to me it's interesting...