First I apologize for the essay that follows; however, the technical background of these barrels can’t be addressed briefly. Most carbon barrels on the market use fiber and resin that do insulate heat. The concentration of heat at the thin wall liner does accelerate wear and will fry in less time than a conventional barrel.

First some points regarding properties of different kinds of carbon fiber.

There are 2 major categories of carbon fiber.

The polymerization of acrylonitrile yields PAN type fiber. This type is common to fishing poles, golf club shafts and most carbon fiber rifle barrels.

Characteristics are medium stiffness and low coefficiency of thermal conduction. This fiber also has a fairly neutral coefficient of thermal expansion.

The polymerization of coal tar pitch or mesophase coal tar pitch yields Pitch type fiber. In its finer grades it is often referred to as graphitic carbon fiber. This fiber is more commonly used in aerospace applications and is 3-30 times more costly than PAN fiber. Characteristics include super high stiffness (modulus) and extraordinary coefficient of thermal conduction. On the downside, pitch fiber has a negative coefficient of thermal expansion. (Heat it and it shrinks!)

Bear in mind that carbon fiber conducts heat in the same manner that fiber optic cable conducts light. It tends to follow the fibers and unless a radical approach is used, it will not cross from fiber to fiber.

416R stainless gun barrels conduct heat at about 21 watts per meter-Kelvin (w/ms*K). PAN fiber of different grades conducts heat at 14-22 w/ms*K. Pitch based fibers conduct heat at 140 – 700 w/ms*K. Pitch fiber will carry a ton of heat at super high speeds.

Traditionally carbon barrels were made to be light. No more, no less. The buzzwords of “heat dissipation” could be construed as marketing. The fiber and resin mixtures in use were garden-variety PAN fibers and low temp boat repair type resins. None of these work very well. Most shooters want more for their money than lightweight mediocrity.  http://www.galleryofguns.com/Shootingtimes/Articles/DisplayArticles.asp?ID=1114  

I am a prairie dog hunter that has burned many barrels in a week on good towns. When I entered the aerospace composites field I began the research and engineering to develop the high heat management fiber application in small arms.

What I have discovered is a way to use the 700 w/ms*K high heat transport graphitic pitch fiber to conduct heat through the wall of the carbon fiber barrel. I use a special filament winding technique and a duplex fiber content to maximize the heat transfer and eliminate the incredible shrinking carbon problem that leads to wandering zero points and 2+” groups. The resin is tough, heat resistant and has a vibration-dampening component.

This link has some charts with the 3^rd party thermal testing data. More technical information is available on the US patent office web site under patent # 6,889,464.

Here’s a comment from the shooter testing the full auto M4 –

“This is going to be the neatest thing since the thong bikini.
Harder than woodpecker lips and it sheds heat at an amazing rate.
After 8 minutes you can hold the barrel easily.  5 minutes after several
strings of full auto it was below the boiling point for spit!!”

Copyright © 2004 Advanced Barrel Systems, Inc.