Barrels

[D.R.D.]

Anyone know how the carbon wrapped barrels fair in this?  Do they cool faster?  Does the carbon absorb or contain the heat?

[survivalshop]

  I believe the Carbon wrapped Barrels are said to be , Heat Dissipators & run much cooler then plain Steel Barrels . Robocop has one , lets see what he has to say about it .

[Robocop1051]

I do have one.

It's still a metal barrel and I can get a 3 to 5 shot string before my barrel is too hot to group... the difference is that I only have to wait a few seconds (30-45) till I'm ready to group again. Also, my barrel is never too hot to touch. This quality does NOT transfer to the gas block or the muzzle device... as I quickly found out the hard way.

[D.R.D.]

Lol. Is it a .308?

[98Z5V]

Yes, it is.  <thumbsup>

[crimsonfalcon07]

Fluting, (when done correctly; mechanically speaking, it's not enough to just cut slots in), provides much more rigidity along a certain axis for a given amount of mass, functioning on a similar fashion to an I-beam.  An easy way to illustrate the basic principles is to look at a ruler.  You can flex it much more easily along one direction than another.  Essentially, the idea is that there's more mass along the width of the ruler to resist flexion than there is along the thickness.  Depending on the direction that force is applied, it has more material to resist flexion.  Thus, a bull barrel of a given diameter will resist flex more than a fluted barrel of the same diameter, because the fluted barrel has less material (lower mass).  However, the fluted barrel will also be lighter, and it will resist flex significantly more than a lightweight barrel of the same mass, because the orientation of the mass is mechanically situated to provide more resistance.

But because mass does actually matter, in practice it becomes more confusing.  For instance, barrel manufacturers most likely just flute barrels by cutting flutes into existing bull barrels, rather than engineering a barrel to have identical flexion resistance for the specific weight.  Thus, you're trading weight for flexion, but at a better rate than you would if you just went lightweight.  It's a compromise that's generally favorable if you want to reduce weight but not lose flexion resistance.  However, even JUST using fluting, it is theoretically possible for a barrel manufacturer to construct a fluted barrel that has lower mass than a bull barrel, but equivalent rigidity.  I am not aware of any barrel manufacturers making such claims, however, outside of the Teludyne folks, who use a very different principle than fluting.

 

Some more food for thought.  Flexion happens along a specifically defined harmonic curve defined by the material and its proportions.  Steel, when heat treated, undergoes physical changes (austenite, martensite, etc), which alter the crystalline structure of the carbides.  Certain of those structures fit very closely together, and as a result of the geometry, also have mechanical support that resists bending.  That's why we heat treat knives or swords, for instance, to a different hardness than we do a tool that needs to resist longitudinal bending and return to true when it does.  More, simple carbon steels often have impurities (which is why forging was important; it would work out the impurities and make the carbon structure more uniform).  Modern metallurgy permits more uniform carbon structure, but the firearms industry by and large has yet to dip into really advanced steels, likely because of the increased cost, but also likely because of tradition.  So, we could get significantly better barrels just from using better quality steel.  But there's also more possibilities.

Because different materials have different harmonic curves, it might be possible to have a lightweight steel barrel surrounded by layers of other materials with precisely placed harmonic curves that would resist each other (think, if steel followed a sin curve, and you had a material surrounding it that followed a cos curve, you might end up with a barrel that would significantly resist flexion).  Of course, then heat transfer might be an issue as well.  There may be other directions to go beyond just materials sciences.  A barrel of the future might be able to use magnetic cooling, for instance, with an electrically generated field driven by the excess gas that gets vented.  For that matter, the tech of the future might involve using the barrel to electrically accelerate the projectile, akin to the principle behind a rail gun.

Anyways, short version is that if you want to save weight without compromising rigidity too much, a fluted barrel is a good bet.  If you want the most rigid and thus accurate barrel, you want a bull barrel, the heavier the better.  And if you want the best of both worlds, you can try a carbon fiber wrapped barrel, or see if the Teludyne folks really can make good on their rather impressive claims.  I certainly look forward to seeing materials science advance to the point at which innovation becomes more cost effective.

[Hueblerking]

SCIENCE!! And at 11:30 too. Damn, crimson, you know a helluvalot more than I do (or probably ever will) about this. It's a good read, though! I still don't know "the rule", but I have a new one: never ever ever ask me to consider looking up trig concepts on a Saturday night again. :-)

I wonder if Belzer feels like we hijacked his thread?!? Belzer, are you still tuned in?

[Robocop1051]

Stay tuned for more info on tensioned barrels. I heard rumor of a tensioned AND carbon fiber barrel in R&D. The company trying this, also makes rocket engine parts for the Virgin space program... he might know his shiit.

[survivalshop]

Stay tuned for more info on tensioned barrels. I heard rumor of a tensioned AND carbon fiber barrel in R&D. The company trying this, also makes rocket engine parts for the Virgin space program... he might know his shiit.

 

 

 

 Yes & all the other fancy materials that were just talked about , will cost as much as if it was made for a space mission , that's why they don't use them . Its not tradition , its cost & what will we pay for it .

   Just what are these barrels going to do , take a 1/4 MOA off your group size, longer barrel life  ? To the Bench rest shooters , this may be the ticket , but for most , its not , the cost may be prohibitive . <dontknow>

[Robocop1051]

 Yes & all the other fancy materials that were just talked about , will cost as much as if it was made for a space mission , that's why they don't use them . Its not tradition , its cost & what will we pay for it .

   Just what are these barrels going to do , take a 1/4 MOA off your group size, longer barrel life  ? To the Bench rest shooters , this may be the ticket , but for most , its not , the cost may be prohibitive . <dontknow>

 

What if I told you the guy doing it was hoping to get the barrel out at a standard "match" or "Ultra-match" barrel price, sub-$400??

[survivalshop]

   Well , we would have to see & taste this thing .  <thumbsup>

[crimsonfalcon07]

I'd be up for one of those.  But yes.  There's definitely a facet that the majority of shooters won't want to pay the currently exorbitant prices for a barrel made out of advanced materials, but then, we're probably not too far from making them cost effective.  For instance, the carbon fiber nanotube armor I previously mentioned runs under 150.  It's a lot more than a comparable steel plate, but pretty close to a kevlar plate, and weighs in at under a pound for IIIA protection.  Carbon fiber nanotube production is getting much more feasible, and offers a lot of interesting possibilities.  Costs for crucible powder steels have been dropping fairly steadily too.  Materials advances will define the next age of technology, in my opinion.