Carbon Fiber Barrel Heat Dissipation Myth(?)

[mk-red]

Hi,
I'm relatively new to long distance shooting - in fact I don't even have my own rifle for it yet.

I have a question when it comes to carbon fiber (cf) barrels.
I'm reading quite a bit that carbon fiber barrels dissipates heat very quickly but I can't possibly see how this is true. I've even observed a couple youtube videos measuring the temperature of the barrel and how its "cooler".

This doesn't make sense to me - if a barrel is capable of faster heat dissipation wouldn't the barrel get warmer quicker?

Shouldn't the appropriate measurement to take be the temperature inside the barrel vs. outside? I don't have a barrel to prove this but I'm currently lead to believe it'll be much hotter inside a CF barrel than any typical barrel...

If I'm wrong please educate me on this.
Thanks!

[sonofeugene]

Look here:

http://www.calguns.net/calgunforum/showthread.php?t=1684712

I think the general consensus was its BS. And there are limitations to wrapped barrels. I wouldn't have one.

[smoothy8500]

The CF wrapped barrels haven't really caught on with PRS or NRA F-class shooters. Those two shooting disciplines generally fire a lot of rounds and would benefit if it were as true as the vendors claim.

I think the CF barrels have their place, such as hunting rifles where shaving a pound or so in barrel weight and keeping the rigidity is beneficial.

[waveslayer]

Good write up by Brian Litz on it. CF does work and shine with less POI shifts as the barrel heats up. Bull barrels do well and just take longer to heat up and retain more heat. Fluted barrels are for weight and have zero heat effects.

Carbon barrels will allow for less POI shifts with heat, as I stated above

Sent from my SM-G986U using Tapatalk

[dreyna14]

If people are measuring the outside temp of a wrapped barrel and claiming it is because the CF dissipates heat they are either trying to sell you something or they are just plain stupid. Carbon fiber has insulating properties and will actually result in less heat dissipation and higher internal temps. If you want a cooler barrel, make it heavier or attach a heat sink made of material that’s conduct heat well like aluminum or copper.

That being said, there could be benefits in that it will allow the barrel to distribute heat more evenly. It will not keep temps down, though.

[G-forceJunkie]

Maybe things have changed, but I got to mess around with a Rem 700 with a carbon wrapped barrel in the late 90's by one of the original players. It shot like a pencil hunting barrel with the groups vertical stringing as it heated up. Thing shot terrible untill I put a pressure pad on the front of the stock putting 2# of pressure on the barrel. Then it grouped great.

[mk-red]

holy cow thank you for the fast replies everyone.

Assuming then that I am going to be repeatedly missing my shots is it safe to assume that I should likely get a heavy barrel?

Final question: I've googled this but I'm still not clear on the differences between a bull-barrel and a heavy barrel. Are they the same thing?

[mk-red]

This 81 year old gramps I've started to go to the range with who struggles to see, hear, and move kicked my a** at long distance and now it's all i can think about.

Building my rifle to learn as much as I can from him before that knowledge is lost forever.

[Stumpfenhammer]

A few things to understand, with the caveat that my experience is primarily with Proof Research's CF barrels (versa Christenson, etc) so my descriptions may be specific to Proof barrels, but I've also discussed the topic extensively with other precision rifle shooters who have credible experience shooting CF barrels from several manufacturers:

(1) There are numerous forms/types of carbon fiber with many variations in heat conductivity, and there are several different methods for wrapping a CF barrel, Proof's for example is completely different than Chistenson's. Which means that the claims of one manufacturer may not be true for another.

(2) Carbon fiber/Carbon is a great insulator (against) the plane of the fiber which is why it's used in Moto GP brake pads and other high-temp insulation roles. However, Carbon Fiber is also a very efficient conductor of heat (along) the longitudinal plane of the fiber.

(3) The high-temp resin developed by Proof and used to bond the CF fibers of a Proof barrel also plays an important role in heat conduction (in other words, it conducts heat).

(4) A proper heat/conductivity measurement of a CF barrel is done both at the surface and with sensors imbedded (during manufacture) at various points along the steel core, as well as with an infrared thermal-imaging camera.

(5) Compared to a steel barrel of equivalent rigidity, the surface of a Proof CF barrel becomes hot to the touch much faster than the steel barrel due to the conductive efficiency of the CF barrel and the increased thermal mass of the steel barrel, conversely, the CF barrel will also cool down much faster. That can be an advantage or a disadvantage depending on your use scenario, but less heat retained in the barrel is generally a positive when it comes to retarding throat erosion.

I used a PROOF CF barrel in 6.5CM to good effect in a competition, I've taken bear, elk, and other critters with CF barrels in 300WM and .308, and I've currently got them on three bolt guns, including a DTA SRS for which I also have steel barrels in the same caliber that I've been able to compare against. They work, and they do conduct heat more efficiently than steel barrels. That said, a CF barrel is not the answer for every application, because sometimes you want a heavier cantilevered weight out front for additional stability (PRS). But for more dynamic shooting-and-moving courses and/or having to hump for long distances (Sniper Challenge) they are beneficial. I've only used steel barrels in the few PRS matches I've shot, but I have friends who shoot many matches a year (PRS and otherwise) and they alternate between steel and CF barrels depending on the course. Then again, this guy won the Wimbledon Cup long-range championship with a CF barrel: http://bulletin.accurateshooter.com/...posite-barrel/ and that's about as static as it gets.

When it comes to understanding CF barrel characteristics (and claims) in depth, one really needs to speak with a materials engineer or scientist (which I've done, with the headache to prove it) who has experience specific to that niche because there are so many technical variables to consider, as well as the fact that a lot of disinformation has been spread over the years. And responding to a previous poster's recollection that 90's CF barrels sucked, that is accurate. But speaking for the current iterations of Proof's CF barrels I can testify that they are highly engineered (much more so than a steel barrel) and are nothing like the CF barrels of the 90's and even the 2000's.

With regards to (steel) barrel contours (CF barrel contours are completely different) here are a few links to help you sort it out (scroll down to see contours compared):

https://cutrifle.com/specs---pricing.html

https://precisionrifleblog.com/2019/01/05/best-rifle-barrel-2/

If you're looking for an excellent match-grade steel barrel I think you can't go wrong with Bartlein or Proof.