Which would be better for accuracy and performance. Not really worried about just weight savings. 26" 6.5 Creedmoor
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Any of the top barrel makers are good to go. It has more to do with the Smith than the manufacturer.
Proof, Bartlein, kreiger, hawk hill... Etc..
Proof, Bartlein, kreiger, hawk hill... Etc..
When you can get 2.5 Bart's for 1 Proof, there isn't even a question...
I have a Bartlein at PVA right now and debating if a Proof CF Savage Prefit would be better or worth buying to compare
Weight reduction is kind of the whole point of a Proof Research carbon barrel. They make a quality barrel, but if weight isn’t a major consideration, they certainly aren’t worth the premium price tag.
How about the other claims:
A stiffer barrel than all-steel, and hence less warping and vibration.
Longer barrel life due to superior cooling.
Improved accuracy.
Greater strength than steel.
No rust.
Nope just weight
It seems to me that 1-4 might be true as long as you are comparing the Proof barrel to a steel barrel with the same weight. If you compare it to barrels with similar contours, the steel barrel will be heavier, but performance wise it will not lose out to a carbon barrel.
Bartlein with a StraightJacket. No question. Carbon fiber is meant for friday night rice burners
Stronger than a heavy barrel, proven heat dissipation, no barrel whip, huge weight savings, jacket available in aluminum, titanium, or stainless. Stainless being the big girl in school. I have them in aluminum and stainless.
If you're not worried about weight, then save the cash and go with a Bartlein. They make an incredible barrel. I have a couple of them on my AI AT. I now use PROOF. The weight savings and more importantly, the shift in balance is worth the premium. I don't know if one is more accurate than the other. Define accuracy. I think the PROOF produces slightly less vertical stringing but both are on par with respect to group sizes IMHO. I do think that the PROOF cools more rapidly when firing strings.
Can't go wrong with either
I agree with Nik up to the vertical stringing thing. If you are seeing vertical then it is more than likely something other than the barrel like the bedding (I know that isn't the case with your AT, but any system that does not have a bonded or 1 piece action/chassis it is possible), the load, or muzzle device effecting harmonics. But that is just my thoughts...
In short, they all are consistent performers.
The following link has some great info about barrels and what makes them more prone to top level accuracy
http://www.accurateshooter.com/technical-articles/barrel-faq/
I have seen about 3 proof barrels on the line and they all shot very well. I think in terms of accuracy potential, the Proof barrels market that they are stiff due to the carbon which is also in place to reduce weight. Not really advantageous in any way unless you need to carry your rifle around all the time. If shooting f-class or benchrest for example, added weight may actually be desirable. Stiffness however can be a good thing. In theory it can lead to less temperamental harmonics. You can increase stiffness by shortening the barrel as well as making it thicker which can be achieved with a conventional barrel as opposed to a carbon wrapped style.
-T
I have both. As stated earlier i cannot tell any difference in the precision of one over the other so if weight/balance is a factor go proof. Otherwise you can go the middle ground route and flute a Bartlein.
The Proof are very cool IMHO.
The Proof are very cool IMHO.
What about are heavier barrels being more accurate? Or does the fact carbon fiber is stronger void that argument?
Generally, the term “heavy barrel” refers to the profile, rather than the weight. A heavy profile will have a larger diameter than a lighter profile of the same length. The increase in diameter results in a stiffer barrel. Increased barrel stiffness is considered to be an aid to potential accuracy. Carbon fiber barrels claim equal or superior stiffness to steel barrels, given similar profiles, while providing a measurable weight savings, among other benefits.
1. Carbon fiber & epoxy is an insulator. Any claim that it helps with removing heat from the barrel is false.
2. Barrel life is reduced due to #1.
3. They use the terms "stiffer" and "stronger" pretty loosely. Compared to what? An all steel barrel of equal weight or an all steel barrel of equal diameter or length? Show me a tensile strength test and a deflection test. And who says tensile strength or stiffness makes a barrel more accurate anyway?
4. Adding mass to a system typically reduces amplitude of vibration and acts as a damper. So by replacing a bunch of steel with light carbon fiber and epoxy, you reduce mass and increase potential for higher amplitude of the vibrations when a round is fired. So does the increase in stiffness (that has not been proven) overcome the reduction in mass enough to minimize and/or dampen the response over a full profile steel barrel?
Carbon fiber wrapped barrels might make sense for a hunting rifle just based on weight savings, but for a match rifle, no...
2. Barrel life is reduced due to #1.
3. They use the terms "stiffer" and "stronger" pretty loosely. Compared to what? An all steel barrel of equal weight or an all steel barrel of equal diameter or length? Show me a tensile strength test and a deflection test. And who says tensile strength or stiffness makes a barrel more accurate anyway?
4. Adding mass to a system typically reduces amplitude of vibration and acts as a damper. So by replacing a bunch of steel with light carbon fiber and epoxy, you reduce mass and increase potential for higher amplitude of the vibrations when a round is fired. So does the increase in stiffness (that has not been proven) overcome the reduction in mass enough to minimize and/or dampen the response over a full profile steel barrel?
Carbon fiber wrapped barrels might make sense for a hunting rifle just based on weight savings, but for a match rifle, no...
I have shot and chambered about all of them. They cool faster? They also heat up faster.
I shoot steel barrels on my competition guns, Proof CF on my hunting rifles. As far as accuracy, it depends how well you can reload. You won’t be able to tell a difference.
I have both and will say my best shooting rifle I have ever owned in my 50 year life has a Proof carbon barrel on it. I have two more Proof barreled rifles and they shoot as well as my other rifles with Bartlein barrel's.
I agree with post above, all my custom hunting rifles from this day forward will have Proof carbon barrel's. They are a weight savings and accurate as can be. Great hunting rifle barrel's.
We have a Proof carbon barrel on my wife's precision rifle and have run some ten round strings with it this last summer. I'm skeptical of the claim that the carbon wrap helps removing heat, but i have to say, accuracy never fell off with the rifle running a 10 round string.
It sounds like you just wanting to experiment and do your own accuracy test. I understand. I say, buy the pre fit and let us know how your accuracy test turns out.
I agree with post above, all my custom hunting rifles from this day forward will have Proof carbon barrel's. They are a weight savings and accurate as can be. Great hunting rifle barrel's.
We have a Proof carbon barrel on my wife's precision rifle and have run some ten round strings with it this last summer. I'm skeptical of the claim that the carbon wrap helps removing heat, but i have to say, accuracy never fell off with the rifle running a 10 round string.
It sounds like you just wanting to experiment and do your own accuracy test. I understand. I say, buy the pre fit and let us know how your accuracy test turns out.
I like this guy. Facts.
My personal opinion still stands, anything steel, wrapped in a Straightjacket
The claims of carbon fiber barrels always need to be understood in the context of weight.
1: Carbon fiber and epoxy has lower thermal conductance. Ok, with respect to what? Maybe with respect to steel, but how about wrt air? Take a thin steel barrel trying to dump its heat into air via a given surface area, and compare to the same barrel profile trying to dump its heat into carbon. Which one is going to loose heat faster? Ok, but air carries the heat away. The carbon fiber wrapping heats up. Now we getting into the second part, which is thermal mass. Yes the barrel is going to heat up, but does the fiber wrapped barrel have more thermal mass than a steel barrel of the same weight? If it does then, weight for weight, you get some thermal dissipation and protection benefits.
2: see 1.
3: have you seen steel barrel manufacturers routinely give the measurements you ask for? No? Why expect it from the carbon guys? Weight for weight, carbon fiber is going to be stiffer and stronger than steel. This is well established. Same profile? Not so much.
4: Vibrational amplitude is driven by bending stiffness and mass. Weight for weight (again), the CF barrel is going to be stiffer than steel, therefore, it will have a lower vibrational amplitude, therefore, for off-node loads, you will have better accuracy because the end of the barrel will have less deviation from optimal as your bullet exits. If you went and optimized your handloads for your rifle and you are taking cold bore shots, you probably will not see that much of a difference. Why? Because handloads are optimized because you've found the right conditions to have the bullet exit on a node in the vibration of the barrel where there is minimum deviation from optimum in the first place.
Now, same profile barrel? Is CF wrapped going to win over steel? No. The steel will likely be just as stiff or stiffer, the extra mass doesn't hurt, and the steel barrel will have more thermal mass and better thermal conductivity too, and it will have less kick because of more mass. Of course, mass is also the penalty you pay.
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Last time I bought a factory fluted Bartlein it cost $475. Last time I bought a Carbon Proof I spent $630.
By the time you cerakote the Bartlein you are pretty close. IMO the proof looks good as is.
Both of those builds came out to 7.3 and 7.5lbs. The Bartlein was a fluted #3 at 25” and the Proof was a Sedero Lite at 24”. Both shot less then 1/2” with factory ammo.
I went with the proof so that I could thread the barrel for hunting suppressed.
By the time you cerakote the Bartlein you are pretty close. IMO the proof looks good as is.
Both of those builds came out to 7.3 and 7.5lbs. The Bartlein was a fluted #3 at 25” and the Proof was a Sedero Lite at 24”. Both shot less then 1/2” with factory ammo.
I went with the proof so that I could thread the barrel for hunting suppressed.
Where can you find Proof barrels for $630?
Optics planet has them on sale for $700’ish then is always running a 10-15% coupons. A couple other vendors do similar.
How is the recoil with the lighter Carbon Fiber barrels? I see some companies now selling weights for their chassis to make them heavier?
Weight for weight, and profile for profile - Which one cools faster?
Recoil really isn’t a concern when you put on a muzzle brake, even most suppressors are good at taming recoil. I just built a 28 nosler that is like shooting a .223 with the muzzle brake on it.
I mean recoil as far as the glass to stay on target to see hits/misses. I was wondering if people with rifles set up for PRS have this problem with the carbon fiber barrels.
Not being snarky, but who cares? They both hold up for long strings of fire.
In fact, disregarding thermal coefficients of whatever.... One real world observation is that the surface of my proof doesn't get as hot and doesn't mirage the scope FoV as bad.
Where did you get yours from?
Exactly. The carbon fiber wrap acts as an insulator. That steel barrel underneath can't get rid of the heat.
What if you got your CF wrap as hot as a steel barrel, would the steel inside be hotter?
There's a subtle mistake in your reasoning.
First, what you really want to do is make the steel part of the barrel cool down faster. So, the real question is, is the steel center in the CF barrel cooling down faster than a thin steel barrel of the same weight?
If you take a pencil steel barrel that weighs the same as the carbon barrel, the surface of the steel barrel will be hotter than the surface of the carbon barrel. This means that the steel barrel is radiating more heat, but thermal radiation is not the fastest way to cool down. The length steel barrel is also in contact with air, but still air is an excellent insulator. This means the barrel isn't cooling down all that quickly.
On the other hand, the steel core of the CF barrel is in direct contact with the CF. CF might have worse heat conductance than steel, but it certainly has better heat conductance than air. Thus, the heat from the steel core gets transferredl relatively quickly into the CF. Now the CF is going to start the heat up. The steel and CF are going to reach an equilibrium that depends on the thermal mass of the CF. Once this equilibrium is reached, the only way to cool down further would be for the CF wrapping to dissipate heat into the air via its surface.
Thus, if you are looking at the CF barrel, there are roughly two periods in the cooling process of the steel core. A faster initial cool down period when the steel core dumps its heat into the CF, then a slower cool down period when the two parts of the barrel reaches thermal equilibrium. The surface of the CF wrap feels cooler for two reasons:
- The temperature is lower than a thin steel barrel because there is more material to take up the same amount of thermal energy.
- The thermal conductance of the CF IS lower than steel, so the thermal transfer into your hand is slower (which is what really gives us the feeling of hot or cold).
I think I will stop here. Didn't mean to write a whole essay but as you might guess, I like physics..... =)
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This is thermo 101 level stuff bud. As a guy who owns an engineering firm that literally deals with heat transfer on a daily basis, I can promise you this is not complicated. I can also promise you that that carbon fiber and epoxy, in this case, is absolutely slowing the heat rejection from the steel.
Alright, then answer a simple question:
How does air, with thermal conductivity of .026 according to this chart, beat even basic epoxy with heat conductivity of around 0.5 - 5?
Maybe its time for you to review some thermo 101.
https://en.m.wikipedia.org/wiki/List_of_thermal_conductivities
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Right after a string of fire, probably
It's going to be a more complex calculation.
Steel has a fairly decent capacity to transmit heat, probably at least 10x better than carbon fibre / epoxy mix. (Assuming Carbon steel)
So working your way out from the heat source (ignition source at the chamber and then the center of the barrel).
With a solid steel barrel, it radiates at lets say 50 units / time to a certain surface area that then gets cooled by air
With a carbon wrapped barrel, it radiates heat at 50 units / time inside the metal center till it hits the carbon fibre from where it then can only get out to the air at 5 units / time
So you would have to calculate how much bigger the surface area of the carbon fiber would need to be to transmit & radiate the same amount of heat.
Also since the thermal interface between the barrel and the carbon fibre is not efficient compared to straight carbon steel, under a heavy string of fire, the actual metal part of the barrel may get a lot hotter due to the initial insulating properties.
It may however not be as important in the long run, as it seems most barrels fail more often than not, due to the throat / chamber area which is going to get blasted with the direct heat / pressure from the round regardless of the barrel type.
You're kidding right? The vast majority of heat transfer from a hot surface to the air is via convection. Thermal conductivity of air has next to nothing to do with it.
OK, let's bring convection into this.
https://durathermfluids.com/calculators/heat-transfer/
Plug in the numbers yourself or use whatever tool you like. I did.
Even under pessimistic assumptions for thermal conductance of the material, more heat gets dumped into the first 2 cm of CF wrap initially than can be carried away by convection.
Proof probably gets better conductivity out of their wrap than the worst epoxy. Let's say they achieve something like 5 w per k m radially along the barrel. In the first seconds after firing they are moving thermal energy from the steel into the 2 cm of cf wrap around the steel at something like 20x the rate of convection.
Yeah, this will slow down as the cf heats up, but by that point it has done its job.
So pretty much it's back to it's all down to wanting to save weight and no other real advantage.
I don't think anybody is going to argue that the same sized barrel in carbon steel would be less efficient at getting rid of heat that the CF wrapped barrel?
So I'm guessing what we actually need is someone to do real measurements on the inside of the barrel / chamber between 2 similar sized barrels and then write the results based on how many shots / speed of shots in the string. As well as measure the temperature of the action / brake on both systems to help eliminate the variable of more heat being dumped into them.
I don't think anybody is going to argue that the same sized barrel in carbon steel would be less efficient at getting rid of heat that the CF wrapped barrel?
So I'm guessing what we actually need is someone to do real measurements on the inside of the barrel / chamber between 2 similar sized barrels and then write the results based on how many shots / speed of shots in the string. As well as measure the temperature of the action / brake on both systems to help eliminate the variable of more heat being dumped into them.
I assumed that the CF barrel is not going to give away heat faster by radiation or convection compared with steel. What I propose is that the steel core transfers heat into CF by conduction. Since the rate of heat transfer by conduction is faster by conduction than convection or radiation, the steel part of the barrel will cool down faster by heating up the CF wrap. Once the wrap heats up, the heat loss is going to slow down, but the steel has been somewhat protected. This will not be as good as a thicker steel barrel, but it will be better than a thin barrel without the wrap.
So, if you think about the core temperature of the barrel over time, I hypothesize that with CF wrap, you will see a steep initial downward slope that changes to a more gradual longer time slope at an inflection point.
With pure steel you will see a uniform smooth slope. The claimed thermal protection is around the initial steep drop.
This is a good point I had not considered the thermal interface. Not sure how much that would penalize the thermal transfer. I would guess it depends on exactly how the barrel is wrapped and the material used.
Right. Agree this could all be pretty academic, though I find it fun to think about.
