Carbon Fiber Barrel Harmonics Video

[cdherman]

I have a pair of Proof CW Savage prefits. Got relatively cheap on sale for like $600. Best shooting barrels I have. But is this a scientifically valid sample? Doubtful.

They are cool looking and a little lighter than would have been the case for a barrel of similar stiffness, per book numbers.
I agree that resin and carbon fibers cannot possibly dissipate heat as fast as steel. Suggestions to the contrary defy all logic. If someone can show good evidence, then I would like it....... CF barrels should be used in hunting guns with low fire rates IMO.....

 

[VinceMule]

I have seen companies go through a learning curve on how much metal to take off, and machining methods to achieve a great product. At the center of a CF barrel is the quality of the barrel being wrapped.

Barrel fluting went through the same process in the learning curve where it was learned that the barrel has to be supported under the cutter doing the fluting, otherwise the barrel will warp as it heats up.

Also, you have to remember that the bore dia can open up as material is removed from the outside. We have seen this issue of the muzzle dia opening up when it is threaded for a muzzle break, taking a .930 muzzle dia down to .625. This issue of the muzzle Dia. opening up does not happen on every barrel and applies to those wanting the ultimate in accuracy. Removing material along the entire length of a barrel and how much it opens up is key, but if it opens up uniformly, the point would be moot. All of these issues could be verified with a LONG Grizzley Rod using a reamer pilot, once the proper size reamer pilot had been determined. Reamer pilots come in sets that are graduated .0002 and gunsmiths order more.

I get my gunsmith to provide me with the exact bore dimension of my barrel by fitting the reamer pilot to the bore. I had a gunsmith some years ago that stamped the bore dia on the outside of the barrel, a practice that is very helpful in load development. A tight bore peaks pressure sooner, and the opposite for a larger dia., and of course we are talking ten thousandths.

If your gunsmith does not purchase sets of reamer pilots to chamber barrels with, you should find another gunsmith! There are only a hand full of gunsmiths in the country that taper bore a chamber and use no reamer pilot. For a precision shooter using CF for extreme long-range shooting, the gunsmith should check bore uniformity and provide you with the bore dia. I would suggest Alex Wheeler.

 

[Mikecr]

Well, there is bore, and then there is groove, and twist rate consistencies, and then there is the functional summation of all as it changes from breach to muzzle.
Sliding a pin down the bore isn't showing everything,, same with slugging, and even air gauging.
The only barrel maker I'm aware of that has the capability to actually measure everything in a barrel is Loather Walther.
That might be with radial ultrasonic. I don't know.