Karl just turned me onto this thread
I've been doing R&D on my carbon barrels with a composites engineer for close to 3 years now. Whoever said that manufacturing processes of modern carbon barrels have the wrong fiber orientation and too resin rich is DEAD ON!
My barrels have a Rock Creek 5R Cut Rifled liner that doesn't get any thinner than .650 at the muzzle and weight about on par with a #3 sporter contour +/- 4 oz.
As far as the technology goes, I'll refrain from speaking of others and focus on my own barrels. First up is fiber orientation. Every layer of composite (notice i didn't say Carbon!) material on my barrel is a continuous piece from tennon to crown. Each barrel as a single seam running the length of the barrel. We also do everything we can with our prep work to ensure that the barrel steel doesn't slip or contract/expand at vastly different rates than the composites material. Next come resin ratios... most carbon barrels have around a 65:35 Resin to Fiber ratio. Resin is a great insulator and traps heat. My barrels are in the 25:75 resin/fiber ratio.
We focus on two things with my barrels. Rigidity (comes from better fiber orientation), and harmonics. When you think of a graphine/carbon fiber fishing rod, it transfer vibrations incredibly well.... Thats the opposite effect you want with a barrel. You want harmonic dampening not amplification/transfer. Thus we don't use 100% carbon fiber.
Our barrels are also cured with no "Induced stress". A very well known carbon barrel manufacturer at one point in time (I believe they still continue this practice) "caps" their barrel with a stainless barrel cap. And they do it while inducing tension into the barrel. Engineering principles states that material under tension is more rigid. But what happens to that tension when barrels heat up and the materials expand at different rates? It creates an unpredictable reaction.
As far as carbon trapping heat.... that's a myth. Formula 1 cars use CF brake rotors because it dissipates heat so much better than steel. It's the resin ratio that is key! My barrels kick off so much heat you get a mirage after 7-10 shots and that carbon will be hotter to the touch than the stainless barrel tennon around the chamber. That's the biggest issue for me and using them in matches. High volume shot strings and mirage is a bad combination.
I quit chasing the weight savings on carbon barrels awhile ago. I could go thinner on contours without issue, but the fact of the matter is with a 7 lb base rifle weight, I can change my grip pressure and EASILY throw a round 1/2MOA sideways one direction or another. The rifle itself is extremely accurate, accuracy is not a function of weight.... but light weight rifles are harder to shoot more accurately as a shooter. If you want to bang animals at 750 and in, you're probably fine with a sub 9 lb well built hunting rifle. Stretching it further than that and you better be on your A game! I prefer a 9.5-10.5 lb gun for long range work. Its worth the extra weight.... you pack 6+ lbs of spotter/tripod up the mountain to up your hunting ability, that extra 1-2 lbs for the added killing ability is well worth it.
Most of my carbon long range rifles end up 7-7.5 lbs base rifle weight with a muzzle brake and 26" barrel.
And building a steel barreled "long range" rifle that weights in at that 7 lb mark sucks! Who likes to spend $3k+ on a gun that has a barrel that opens up from .5 MOA to 1.5 MOA after 6-7 shots? If you're shooting long range, you need to be shooting a lot, and waiting 15-20 minutes for a sporter contoured barrel to cool down after a few shots is retarded... I won't do it lol
Hope this helps some of you!
Mike
