Does anyone have any experience with Proof Research barrels? They are expensive, but may be a good way to get a light barrel with a heavy profile. Best of both worlds and all that.
Proof Research???
- Thread starter scimitar2
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Metals and carbon fiber don't like each other. Over time they will separate. So much that Formula 1 cars use carbon fiber machined fasteners instead of metal ones to secure components. Christensen in Switzerland tried marketing carbon lined barrels for years and had nothing but problems. Unless Proof Research have reinvented the wheel (which is possible) be very careful with getting first hand long term testing results.
"Ex Umbris Venimus"
"Ex Umbris Venimus"
I've had one on my AR from proof research for over 3 years and its a shooter. I did it for the weight and haven't looked back. Sigma is right about carbon fiber being a reactive component but Mike has done his research and I think the only complaint i've heard from anyone is the price tag. Its really up to you and if the weight is worth the price then I don't think you will be disappointed with their product. My AR was a custom build from the ground up and its sub MOA. Some days less than half MOA but most days just Sub moa. Mostly because of me behind the gun being the limiting factor.
It's not the fiber that's really the issue, but the matrix component of the composite. Use the right surface treatment and match the thermal expansion coefficients at the surface intersection and you're fine. I'm really interested to get my hands on one of their stocks, the construction and profile look very interesting.
I bought a carbon wrapped ABS/Rock Creek barreled action from Dan Muller. (Proof bought the patent from ABS so I'm assuming they are the same)
It is chambered in 6.5-284 and I have approximately 800 rounds through it. It has shot pretty much every bullet I have tried sub 0.5 MOA or better, so it certainly hasn't affected my accuracy. The main reason I got it was for weight savings plus it was a hell of a deal. As for their claimed lengthening barrel life, I guess I won't know for at least another 1000 rounds or so. I only use it for hunting and informal range sessions, so it doesn't get shot too much.
It does seem to cool to the touch faster than my .243 with a regular varmint contour, but that is certainly not scientific evidence. However, it seems to cause worse mirage than a normal barrel, when shooting extended sessions. Again, that is just an observation not a lab test.
Do I like my barrel? Yes, it shoots great and is very light and works great on my hunting rig.
Would I spend $900 bucks for a new one? No, I would just go with a traditional barrel in a smaller contour.
Whole rig weighs 11.4 lbs with scope (no bi-pod) which is good, considering the adjustable stock is pretty heavy, as is the Zeiss. I think for a dedicated hunting rig it serves a purpose. Would I recommend it for a dedicated competition rig, probably not.
It is chambered in 6.5-284 and I have approximately 800 rounds through it. It has shot pretty much every bullet I have tried sub 0.5 MOA or better, so it certainly hasn't affected my accuracy. The main reason I got it was for weight savings plus it was a hell of a deal. As for their claimed lengthening barrel life, I guess I won't know for at least another 1000 rounds or so. I only use it for hunting and informal range sessions, so it doesn't get shot too much.
It does seem to cool to the touch faster than my .243 with a regular varmint contour, but that is certainly not scientific evidence. However, it seems to cause worse mirage than a normal barrel, when shooting extended sessions. Again, that is just an observation not a lab test.
Do I like my barrel? Yes, it shoots great and is very light and works great on my hunting rig.
Would I spend $900 bucks for a new one? No, I would just go with a traditional barrel in a smaller contour.
Whole rig weighs 11.4 lbs with scope (no bi-pod) which is good, considering the adjustable stock is pretty heavy, as is the Zeiss. I think for a dedicated hunting rig it serves a purpose. Would I recommend it for a dedicated competition rig, probably not.
Nice rifle and very interesting information. If this pans out it may be the next big. innovation!
Carbon Fiber is an excellent insulator, so you're basically wrapping a big blanket over the barrel.
It's not cool to the touch because it magically sloughed off all the heat...it's cool to the touch because it's keeping it all inside.
It's not cool to the touch because it magically sloughed off all the heat...it's cool to the touch because it's keeping it all inside.
Some research suggests otherwise, that CF in fact has good heat conductivity.
That, plus one shooter's observation that mirage over the CF wrapped barrel is worse than a similar steel barrel, suggests that the CF conducts and sheds heat very well.
It's not ceramic or fiberglass, it's carbon.
Joe
That, plus one shooter's observation that mirage over the CF wrapped barrel is worse than a similar steel barrel, suggests that the CF conducts and sheds heat very well.
It's not ceramic or fiberglass, it's carbon.
Joe
There is a reason I use carbon fabric blankets to insulate items and shield welding sparks from burning and destroying the material under them. We also use carbon fabric for suppressor mirage covers.
I did a little additional sleuthing on this myself.
While I did in fact read about some budding new special technology that is able to achieve very high thermal conductivity from CFRP, standard structural CFRP is about 10 watts/meter per degree Kelvin. Compare that to ~43 W/m-K for chro-moly steel and ~25 W/m-K for 416 stainless.
Trouble with this figure, is it relies heavily on what type of epoxy resin was tested, what ratio was used, how well it was laminated, how and how well it was cured.
Nonetheless, standard common sense applies. I've been around CFRP quite a lot, and have a feel for it:
If you hold a piece of aluminum up against a grinder wheel, it only takes a second before it's too hot to hold.
Steel? You can grind it a good bit before it's too hot.
Titanium? You can grind on it a good long while before it burns your fingers.
Carbon? Takes a real long time.
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Assuming that the above is true (with an N=1, that is a big assumption but lets go with it anyway) and that during the experiment there was equal grinding on all materials tested, then this set of observations pretty well describes how Carbon fiber could be used in the way described. It is true that if carbon fiber had a high heat conductivity then it would feel hotter to the touch after many rounds down the tube. That is just a fact of how things work. Ice is cold because it is pulling heat from your hand. Hot barrels are hot because they are transferring heat to your hand. I will not counter the claim that carbon fiber "acts as an insulator." However, I do not believe low heat conductivity allows for this property. Rather (given the above observation) I would counter that it is due to the high "specific heat" of carbon fiber that allows it to both act as an insulator in certain applications and to allow the barrel of a firearm to run cooler for longer shot strings. Conductivity and insulation are bandied about much without any definitions- everyone knows what an insulator is right? But, in the observations above, the poster has basically argued that steel is a better insulator than aluminum- takes longer to get hot when ground upon. "But, but," you say "steel is a conductor." Well, "specific heat" is a scientific term for the amount of energy required to raise a defined mass (scientific term for a defined amount of matter- ie "stuff") a defined number of degrees. For example, it takes 4.186 joules (unit of energy) per gram (unit of mass) of water (the matter in question) to raise the temperature one degree Celcius. Why is carbon fiber act as a good insulator? It takes much more energy to raise the temperature of one gram of carbon fiber one degree than it does an equal amount of steel. Not because it reflects it back like an emergency blanket, but because it absorbs it. How does carbon fiber wrap keep the steel barrel cool? The specific heat of 420 stainless is 460 joules per kg per deg C (Properties Of Stainless Steel). The specific heat of carbon fiber (http://www.toraycfa.com/pdfs/T300DataSheet.pdf) is 795 joules per deg C (4.186 joules per Calorie). Given some amount of entropy (loss of energy, like a Universe tax) in the interface between the two materials and it may take as much as 2x more energy to increase the temperature of carbon fiber than it does steel.
According to the same data sheets, carbon fiber has ~ 2.4x lower thermal conductivity than 420 steel (10W/m*K compared to 24). Convert from cal/s (0.025) to cal/hr (90) then convert to watts (0.1) [http://www.unitconversion.org/power/watts-to-calories-it--per-hour-conversion.html], then convert from cm to m (x100). Units of C are equal to Units of K, although the scales have different zeros.
In summary, carbon fiber can keep the steel core of a rifle barrel cool because it takes more energy to heat up the same mass of carbon fiber than it does steel. Because of this property, the entire barrel stays cooler longer.
[Aside] Copper has a much higher specific heat than aluminum, which is why you do not see aluminum wiring in houses any longer. Additionally, fiberglass has a much higher specific heat than cotton (and a much higher ignition temperature), which is why you no longer see cotton insulation in housing. The combination of aluminum wiring and cotton insulation led to many housing fires before the current combination (copper and fiberglass) was mandated by law.
[Disclaimer] The links provided are the first that I found doing a basic google search. I am not a materials scientist, and I have no association to Proof Research. However, I did take a few chemistry courses in college and I did stay at a Holiday Inn Express last night.
Great post.
Trouble is the low thermal conductivity doesn't allow for the heat to wick away from the core very quickly.
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Well, hell... might have to ponder this more. We can all agree a water cooled bore would be great...and water has low thermal conductivity too.
Trouble is the low thermal conductivity doesn't allow for the heat to wick away from the core very quickly.
ETA:
Well, hell... might have to ponder this more. We can all agree a water cooled bore would be great...and water has low thermal conductivity too.
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And a very high specific heat- ~10x higher than steel. I look at this carbon fiber wrapped barrel as a play on the water cooled barrel, though much less efficient.
The low thermal conductivity of water is not a good thing for a water cooled firearm. Once the water gets hot, it stays hot for a long time, much longer than steel will. It is the high specific heat of the water (the ability to absorb a lot of energy with only a modest change in temperature) that makes a water jacketed barrel run cool[ish].
Anyone know what (if anything) happens to a water cooled machine gun if fired until the water in the jacket is substantially hotter than boiling? Honest question, I really do not know (though I have a guess...).
It (CF wrap) is not magic, but probably does not work quite as well as advertized. For slow fire, the higher specific heat of the duplex barrel material could keep the whole barrel cooler. However, under sustained rapid fire the lower thermal conductivity may be problematic (as seen in at least one youtube video).
Old post. This topic has been beaten to death.
http://www.snipershide.com/shooting...172524-carbon-wrapped-barrels-more-proof.html
We had a Proof Research barrel in here for some testing. Actually, we were asked to build a rifle for a magazine article using the Proof barrel and Pierce's new Titanium action. It was a Saturn blank in 1:11 twist with Proof's carbon treatment. Rifle shot great. Our experience with carbon wrapped barrels in the past (meaning like 3+ years and older) wasn't so great.
So, performance of our single unit sample was very positive. Customers coming into the shop were interested in the "new" technology and all thought the truly light weight tactical rifle was super cool. But then most balked at the price and were not too interested in being what they felt was a "guinea pig" or "beta tester". These were terms several customers used. The thought was only time will tell and that is a lot of money to lay out for something you don't know how it will really perform over time. I'm pretty confident that Proof has got the products much better off than things might have been years ago.
Mark
So, performance of our single unit sample was very positive. Customers coming into the shop were interested in the "new" technology and all thought the truly light weight tactical rifle was super cool. But then most balked at the price and were not too interested in being what they felt was a "guinea pig" or "beta tester". These were terms several customers used. The thought was only time will tell and that is a lot of money to lay out for something you don't know how it will really perform over time. I'm pretty confident that Proof has got the products much better off than things might have been years ago.
Mark
I have a Proof custom build in 7 WSM. It is a lightweight hunting rifle. ABS wrap on Bartlein barrel. Actions are Defiance.
I was routinely shooting clay pigeons at 500 yds with it this weekend. Shoots very well and I own rifles from many top manufacturers - GAP, APA, DTA, Blaser, SAC, etc. Shoots as well as any of them and better than I do.
I do think shooting fundamentals are more important because it is light weight.
I was routinely shooting clay pigeons at 500 yds with it this weekend. Shoots very well and I own rifles from many top manufacturers - GAP, APA, DTA, Blaser, SAC, etc. Shoots as well as any of them and better than I do.
I do think shooting fundamentals are more important because it is light weight.
I have a Proof barrel in .375 CheyTac and I am hooked. For these larger rifles, it's the way to go. My weapon is about ten pounds lighter on the hoof than others of its kind with no known drawbacks as of yet other than the price. For the product I received, however, I am happy to pay the price. In fact, I am going to order a couple more to have in stock just in case . . .
Caylen won the 2013 Oregon sniper challenge with one. (in .308 IIRC).
Comparing the proof carbon to other examples of carbon really requires knowledge of the product that nobody here has. Carbon alone is a great thermal conductor, resins are great insulators. Without knowing the exact composite, we are all guessing.
Comparing the proof carbon to other examples of carbon really requires knowledge of the product that nobody here has. Carbon alone is a great thermal conductor, resins are great insulators. Without knowing the exact composite, we are all guessing.
There are many experts on public forums who speak opinions based on whim and emotion and are quick to dismiss, and even insult, others. I am neither of these. I am not an expert in marksmanship, rifles, ammo, or reloading but the Ph.D. on my wall labels me somewhat of an expert on chemical physics. Last year I wrote a short communication on carbon fibers and how they are a research focus in many arenas due to their ability to very rapidly conduct heat so I will not recount those data. I will add, however, based on many other comments that I have read, that carbon is a unique animal and can produce a wide range of observable properties: It can be used as an abrasive or a lube, an insulator or a conductor. So this material can be confusing and misleading. There are many variables that contribute to these differences in properties but the one which is perhaps the most influential is crystallinity. Charcoal, for example is amorphous thus having no crystallinity, i.e. no repeating units, and has never been accused of being a good conductor. Diamond, another form of carbon, crystallizes in a complex cubic-F lattice. Graphene, also carbon, is comprised of repeating six-carbon-atom rings in a honey come structure. Crystallinity has a tremendous influence on thermal conductivity but I’ll spare the audience the boring details and quit jabbering on . . .
I have a Proof barrel on a .375 CheyTac and took some measurements this weekend using an IR thermometer before and after shooting several rounds. The air temperature was around 56 degF and all portions of the barrel initially were equal to or slightly below that value. I slow fired about 25 rounds then “rapid” fired three in a row. I took readings at various locations on the barrel, inside the barrel from muzzle side, and inside the chamber by aiming and locating the laser accordingly. The max temperature of the carbon fiber was 71 degF and the temperature of the stainless steel inside the barrel at about the same location (about two and a half inches inside the muzzle) was only 73 degF. The hottest portion of the entire barrel was the last inch or so of the barrel, which is entirely stainless without any carbon fibers, reaching 91 degF. The breech temperature measurements never exceeded 70 degF. The entire session was conducted in the direct sunlight but, as I mentioned, the air temperature was pretty cool.
It is apparent that the carbon fiber wrapping was in fact doing its job of readily conducting heat. The areas of the barrel which are wrapped were consistently cooler than those without wrapping. The portion of the barrel which was measured from the inside was in agreement with the same region outside the barrel thus indicating that the material is not insulating and is allowing the heat to be rapidly released to the environment. Of course, I have about 50 rounds through the barrel so I cannot attest to the resilience of the material but as time progresses, or if something happens, I’ll surely post an update. And this is my barrel which I hope to use for a very, very long time so I will not “push” the envelope for the sake of curiosity.
I am neutral with respect to this product. I have no interest in marketing for or against the company; rather, I am merely reporting my observations for the benefit of those who are interested.
I have a Proof barrel on a .375 CheyTac and took some measurements this weekend using an IR thermometer before and after shooting several rounds. The air temperature was around 56 degF and all portions of the barrel initially were equal to or slightly below that value. I slow fired about 25 rounds then “rapid” fired three in a row. I took readings at various locations on the barrel, inside the barrel from muzzle side, and inside the chamber by aiming and locating the laser accordingly. The max temperature of the carbon fiber was 71 degF and the temperature of the stainless steel inside the barrel at about the same location (about two and a half inches inside the muzzle) was only 73 degF. The hottest portion of the entire barrel was the last inch or so of the barrel, which is entirely stainless without any carbon fibers, reaching 91 degF. The breech temperature measurements never exceeded 70 degF. The entire session was conducted in the direct sunlight but, as I mentioned, the air temperature was pretty cool.
It is apparent that the carbon fiber wrapping was in fact doing its job of readily conducting heat. The areas of the barrel which are wrapped were consistently cooler than those without wrapping. The portion of the barrel which was measured from the inside was in agreement with the same region outside the barrel thus indicating that the material is not insulating and is allowing the heat to be rapidly released to the environment. Of course, I have about 50 rounds through the barrel so I cannot attest to the resilience of the material but as time progresses, or if something happens, I’ll surely post an update. And this is my barrel which I hope to use for a very, very long time so I will not “push” the envelope for the sake of curiosity.
I am neutral with respect to this product. I have no interest in marketing for or against the company; rather, I am merely reporting my observations for the benefit of those who are interested.
Ok I have a dumb question.
Claims of longer barrel life? Your throat get's eatten away by powder gasses no matter what. You might still have good rifle but dont you still have to cut the back of the barrel of and rechamber it, but you kinda running into the carbon fiber wrapped part of the barrel?
Or is the barrel life reference to when you have a higher cyclic rate i.e. full auto and it is able to remove enough heat from the chamber that it lasts longer?
Claims of longer barrel life? Your throat get's eatten away by powder gasses no matter what. You might still have good rifle but dont you still have to cut the back of the barrel of and rechamber it, but you kinda running into the carbon fiber wrapped part of the barrel?
Or is the barrel life reference to when you have a higher cyclic rate i.e. full auto and it is able to remove enough heat from the chamber that it lasts longer?
I have been shooting a proof research barrel for about 8 weeks now (~150 rounds). I have no movement or POI change after a rapid series of shots. It shoots every bit as well as my other high end barrels.
Hard to say on cooling, but neither the barrel where wrapped, nor the exposed steel have ever gotten real warm. My 'fast' string might be 8-12 rounds/minute.
Time will tell on barrel life and durability, bit it is light and shoots. I have enough breech to rechamber it without getting into the carbon wrapped area.
Hard to say on cooling, but neither the barrel where wrapped, nor the exposed steel have ever gotten real warm. My 'fast' string might be 8-12 rounds/minute.
Time will tell on barrel life and durability, bit it is light and shoots. I have enough breech to rechamber it without getting into the carbon wrapped area.
As I posted above, I have an ABS/Rock Creek carbon wrapped barrel chambered in 6.5-284.
I now have around 900 rounds down the tube and I have lost around 100 fps across the board on all my loads. The throat is beginning to erode, which is pretty common for this caliber right around the 800-900 round mark.
140 Amax/140 Berger were shooting around 2950 now around 2850.
It still hammers, just a tad slower.
So for my small sample size of 1, it doesn't look like I will be gaining any appreciable barrel life.
Hope that helps the discussion.
I now have around 900 rounds down the tube and I have lost around 100 fps across the board on all my loads. The throat is beginning to erode, which is pretty common for this caliber right around the 800-900 round mark.
140 Amax/140 Berger were shooting around 2950 now around 2850.
It still hammers, just a tad slower.
So for my small sample size of 1, it doesn't look like I will be gaining any appreciable barrel life.
Hope that helps the discussion.
It doesn't seem that these barrels are worth the price for a "barrel burner" but in order to conserve weight in a large weapon like the CheyTac, so far they seem great. The idea of shaving ten pounds is worth the price to me.
Santee, did you have any trouble in load development? Were the nodes spaced similar to your previous barrel (assuming the previous barrel was SS)?
Santee, did you have any trouble in load development? Were the nodes spaced similar to your previous barrel (assuming the previous barrel was SS)?
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Load development was a breeze. I found it hard to find any combination it didn't like. I attribute that to the high quality Rock Creek barrel liner as well as Dan Mullers gunsmithing skills. As I said, I got a great deal on the barreled action, so the "high cost" of the barrel didn't factor in for me.
This has been my only barrel chambered for 6.5-284, so I can't compare it to any previous experience. But the weight savings on this hunting rifle have been appreciated.
Once the barrel it toast, I am leaning toward re-barreling it with a regular SS #5 fluted in .280 AI. Should be comparable in weight, at a lower cost.
Curious to know what load you're using. I have 2 6.5-284's, one with a 28" Benchmark/Proof Barrel and one with a 28" Hart barrel. I have a load at 2950fps with the Hart barrel - hammers but with some ejector marks/primer flattening.
Been using H1000 in the Proof barrel with no pressure signs and getting just over 3000fps. Barrel is noticeably cooler with strings of fire.
Shoot the H4831SC load and the barrel gets hot quick/brass comes out hot, etc.
I think the Rock Creek barrels were one of the first ones to be used when Proof technology was ABS. I think they have refined the process since.
I was using around 50.5-51.0 grains of H4831SC with the 140 VLD and 140 Amax. It was a fairly high pressure load, which probably accounted for the short barrel life.
H1000 or Retumbo would probably be a better route to take with a longer barrel.
Thank you for this extremely useful analysis. I've been searching all over the internet looking for the exact information you presented. Looks like I'll be buying two (16" AR-15 and 22" DPMS 308). Thanks again!
