Proof research barrels

[fredo]

Still not seeing "alot more" of anything?

Step down in contour, and you're near & close in weight. But if those extra ounces of pure steel still cause you to lose sleep, send the barrel off to someone legit (like Kampfeld) and have him flute the crap outta it for a around buck & a half. You'll still have a couple hundred in your pocket, and you should then be able to make it over that next hill, thanks to those precious ounces lost...

If it does boil down to aesthetics, then that seals the deal for me, as I happen to think carbon wraps look stupid. But then again, who am I to judge, since I've got rifles in nearly every color under the rainbow

Obvious that I'm being 'devils advocate' here, but I also AM a potential customer! Just haven't yet seen anything in the way of performance gain that a wrapped barrel earns, for twice (at least) the price?

P.S., for all the 'light rifle' guys...

There are some svelte, dandy stocks that won't accept anything more than a #4 contour. So, that pretty much precludes using one with a (fat) wrapped barrel, as even the 'light' sendero will overstuff the skinny barrel channel.

Food for thought!

 

[rpierce]

Well heres one I finished up for load development on tonight in a 28 nosler with a proof carbon. 3 shot group at 400 yards off a bipod. The first shot was with a clean and cold bore. Pretty impressive 1.014"/.242 moa group considering that. 81.1 gr of VV N570 w a 195 berger at 3075 fps and zero pressure. Ive tested this node and its consistently single digit es. 3130 was another node with low single digit es, no pressure, but it didn't shoot quite as good. As far as the cost of the barrels its not really twice the price of a steel barrel. A fluted steel barrel is around 450-500. Carbon is around 750. The problem with going with a super light steel barrel is you don't have enough meat for big threads for the big calibers. Theres articles explaining what can happen with that. 1/2x28 or 9/16x24 is no where near optimal for a 7mm, .30, or .338 cal. With the proof barrel I put my self timing 5 port on it with 3/4x24 threads. If a customer wants my self timing 3 port the chamfer on the back of the nut blends in seamlessly with the proof sendero contour.

 

[Jesse Gietzen]

this thread has a lot of great questions and observations. and here i am, chiming in again. no, i don't work at proof anymore.

Do they last longer? yes, but i attribute that primarily to the cut rifling process vs. button rifled and not the wrap.
Cool faster? yes. the helical (proof and carbonsix) weave takes longer to heat up and cools faster. the "latticed" weave (christensen) should insulate heat (not desirable) but produce higher stiffness (as i understand it, at least. never worked with the latticed weave barrels or seen tests on them).
More accurate? if i had to guess (i don't specifically KNOW), i would suspect a steel barrel should have a higher accuracy ceiling, all other things being equal. i'm talking groups you measure with calipers, not 3/8 groups. the heat treated steel still has SOME stress in it, and contouring the steel down does bring some of it out sometimes. even with cut rifling.

Obviously the technology to assemble them is costly, hence the high price. But, how does that added expense benefit the end user?

good questions. i think they're a bit of a novelty and/or niche product. do they perform? absolutely, consider why. proof manufactures cut rifled barrels in house. christensen uses shilen barrels. they do not begin life as mass produced factory barrels. i do see ways that carbon outperforms steel, and ways that steel outperforms carbon. steel DOES get hotter faster (again, not sure about christensen), and groups open up. this is with ar and sporter profiles, by the way. match profiles may eliminate this advantage at the cost of weight. on the other hand steel IS stiffer, and is going to support a can better without drooping.

i've handled a 28" carbon fiber barreled rifle plus 2" brake and i honestly don't believe you can get 30" of all steel to feel that light outside of a pencil profile.

There has been a lot of talk over the years to the benefits of CR wrapped barrels. They're lighter, they're stiffer, they cool faster, but those claims require you to read the fine print and once you do, you quickly realize it's more about word trickery and how they come about making any of those claims. very good observations and i like your thought process. the claim is "stiffer by weight" which i never liked. barrels are measured by mass (contour dimensions), and carbon fiber is NOT stiffer by mass, only by weight. and most hunting rifles do NOT have sendero barrels, so the lighter claim also has an asterisk.

Once you boil off all the BS it pretty much comes down to aesthetics. Personally, I like how they look, especially when the brake matches the contour of the barrel, but short of being more appealing to the eye for some of us, they really do nothing else better than a all steel barrel, and in all actuality, by the time they turn the barrel down and wrap it, the risk of there being potential problems with the barrel are likely higher.

they definitely heat slower and cool faster. no asterisk there. i've seen test results where we ran steel and carbon shot for shot and measured accuracy and heat until the resin failed. i don't believe i should share specific results but the carbon barrel outperformed the steel barrel in that test and it was not close. until resin failure the carbon barrel kept accuracy much, much better than the steel barrel. it was a torture test with full auto mag dumps, mind you, so doesn't necessarily apply to bolt guns. it still offered a lot of information. carbon shrinks as it heats, unlike steel. this is not an insignificant factor as the barrel heats up.

now, as for the "risk of potential problems" comment, as a more complex component, yes. it's impossible for there to be fewer things to potentially go wrong. but for the most part, those issues have been satisfactorily addressed.

I used to work on aerospace composites for a living. They’re not simple and there are things that can go wrong that you cannot see. That’s not to say proof is unreliable, but that’s the nature of composites. I really have no idea, as I’ve not used proof’s barrels, but my initial reaction to them is that dropping down a countour is a much more sensible way to go.

mixing carbon fiber and steel in a precision barrel definitely presents a large number of obstacles. many of those are overcome, and many you still have to deal with. it's not easy, which is why you don't have a lot of companies doing it. if you know the pros and cons of each, it definitely helps make a decision. i personally prefer steel, ONLY because weight is something i see as a positive. i wouldn't want a steel pencil, though, because the carbon fiber won't have an accuracy limit of 3 shots. now, for a hunting rifle, 3 shots may be 2 more than you need. usage makes a difference for sure.

 

[fredo]

Wow, most excellent reply...thank you!!!

Some great takeaways from this thread, I can see where a wrapped barrel might be advantageous for a specific type build. From reading above I might could prolly justify a wrapped barrel for a large caliber, long barreled super hotrod...

For one, a brake would shoulder better on the fat barrel

Second, you'd get all your fps from the long barrel, without getting overly front heavy

Third, it may dissipate heat better during a long string of fire

Still, aggressive fluting on a heavy contour steel barrel would check those same boxes. But, at least I can now envision possibly going with a wrapped barrel on a future large caliber build, if the spirit ever moves that way. Mebbe once this fascination with small caliber fire breathers wears thin? Although the carbon wrap still looks stupid...

Thanks again for the replies...interesting topic!
Happy Thanksgiving, ALL!

 

[Ledd Slinger]

Wow, most excellent reply...thank you!!!

Some great takeaways from this thread, I can see where a wrapped barrel might be advantageous for a specific type build. From reading above I might could prolly justify a wrapped barrel for a large caliber, long barreled super hotrod...

For one, a brake would shoulder better on the fat barrel

Second, you'd get all your fps from the long barrel, without getting overly front heavy

Third, it may dissipate heat better during a long string of fire

Still, aggressive fluting on a heavy contour steel barrel would check those same boxes. But, at least I can now envision possibly going with a wrapped barrel on a future large caliber build, if the spirit ever moves that way. Mebbe once this fascination with small caliber fire breathers wears thin? Although the carbon wrap still looks stupid...

Thanks again for the replies...interesting topic!
Happy Thanksgiving, ALL!

You can flute a heavy contour barrel all you want and it's still going to weigh significantly more than a CF with the same contour. Be lucky to save 6-8oz on a large barrel with fluting. CF barrel you can save close to 3 lbs depending on length and cotour comparison.

My AG Composites CAT 700 sporter all carbon fiber stock for Rem 700 LA BDL weighs 22 oz with sling studs. Strongest stock you'll ever feel too. Cant warp the barrel channel in the slightest manner while twisting with all your strength. Wood or fiberglass stocks can't come close to that weight unless you gut them so bad their safety and inegrity is greatly compromised.

The main purpose of CF is getting weight savings without compromising strength. You see it all over in archery products, rifle accessories, high end automobiles, aeronautics, etc. If it was just for looks, was not as strong, or performed poorly in any given product, then people wouldn't pay the extra money for it. But the fact is CF serves its intended purpose quite well.

 

[fredo]

You can flute a heavy contour barrel all you want and it's still going to weigh significantly more than a CF with the same contour. Be lucky to save 6-8oz on a large barrel with fluting.

My AG Composites CAT 700 sporter all carbon fiber stock for Rem 700 LA BDL weighs 22 oz with sling studs. Strongest stock you'll ever feel too. Cant warp the barrel channel in the slightest manner while twisting with all your strength. Wood or fiberglass stocks can't come close to that weight unless you gut them so bad they have no strength left.

CF is mostly about weight savings without compromising strength. You see it all over in archery products, rifle accessories, high end automobiles, aeronautics, etc. If it was just for looks, then people pribably wouldn't pay for it.

Depending on stock design & fill, I may WANT that extra weight up front to balance the rifle...

Balance is MUCH more important (to me) than simply shaving as much weight as possible. In short, I'd rather tote a balanced 9 lb rifle, than an azz heavy, nose flippy 8lb rifle. So I'll use whatever length/contour/fluting config it takes to achieve that harmony...

P.S. AG Composites lists their CAT stock @26-27oz. You musta got an anorexic one?
http://agcomposites.com/carbon-all-terrain-cat-rifle/

 

[Ledd Slinger]

Depending on stock design & fill, I may WANT that extra weight up front to balance the rifle...

Balance is MUCH more important (to me) than simply shaving as much weight as possible. In short, I'd rather tote a balanced 9 lb rifle, than an azz heavy, nose flippy 8lb rifle. So I'll use whatever length/contour/fluting config it takes to achieve that harmony...

Totally agree. Balance is important. A lightweight rifle can be balanced just the same as a heavy rifle. The CF stock I am using on my 300 NMI build is made by Christensen Arms and is 10 oz. heavier than my AG Composites, with that weight in the rear. This will help compensate for a large brake on the barrel and shift the fulcrum point rearward. I will sometimes drill and add weights in spots. Of course a scope needs to be mounted and magazine loaded with rounds to get a true sense of balance. Nice thing about CF stocks is that they are so strong, you can put holes anywhere in the butt or inletting and not have to worry about compromising strength.

 

[WestCo]

What kind of speed are you getting with the 215 Berger.

I'm getting right around the 3000 fps range. I'd have to look to verify due to too many other rifles I've been reloading for and shooting since doing all of my load development on the 30 Nosler. Let me know if you have any other questions and I can look up my specific data if you want. Feel free to PM as well.

 

[dcali]

this thread has a lot of great questions and observations. and here i am, chiming in again. no, i don't work at proof anymore.



good questions. i think they're a bit of a novelty and/or niche product. do they perform? absolutely, consider why. proof manufactures cut rifled barrels in house. christensen uses shilen barrels. they do not begin life as mass produced factory barrels. i do see ways that carbon outperforms steel, and ways that steel outperforms carbon. steel DOES get hotter faster (again, not sure about christensen), and groups open up. this is with ar and sporter profiles, by the way. match profiles may eliminate this advantage at the cost of weight. on the other hand steel IS stiffer, and is going to support a can better without drooping.

i've handled a 28" carbon fiber barreled rifle plus 2" brake and i honestly don't believe you can get 30" of all steel to feel that light outside of a pencil profile.



they definitely heat slower and cool faster. no asterisk there. i've seen test results where we ran steel and carbon shot for shot and measured accuracy and heat until the resin failed. i don't believe i should share specific results but the carbon barrel outperformed the steel barrel in that test and it was not close. until resin failure the carbon barrel kept accuracy much, much better than the steel barrel. it was a torture test with full auto mag dumps, mind you, so doesn't necessarily apply to bolt guns. it still offered a lot of information. carbon shrinks as it heats, unlike steel. this is not an insignificant factor as the barrel heats up.

now, as for the "risk of potential problems" comment, as a more complex component, yes. it's impossible for there to be fewer things to potentially go wrong. but for the most part, those issues have been satisfactorily addressed.



mixing carbon fiber and steel in a precision barrel definitely presents a large number of obstacles. many of those are overcome, and many you still have to deal with. it's not easy, which is why you don't have a lot of companies doing it. if you know the pros and cons of each, it definitely helps make a decision. i personally prefer steel, ONLY because weight is something i see as a positive. i wouldn't want a steel pencil, though, because the carbon fiber won't have an accuracy limit of 3 shots. now, for a hunting rifle, 3 shots may be 2 more than you need. usage makes a difference for sure.

Thanks for the detailed reply. The one question I've been trying to figure out, but nobody has ever (to my knowledge) addressed in public is this:

Traditional aerospace composites have a matrix that is basically plastic, and poor heat conductor, that surrounds the carbon fibers. For example, when building a simple thin plate, you cannot reliably even get electrical conductivity from one side of the plate to the other. (I know, heat vs electrical is not exactly the same, but they go hand in hand).

And wound structures tend to be heavy on matrix relative to laminates (I was told that Proof barrels are wound?). What is Proof doing that mitigates this? Is it a specialized matrix? Some sort of trick? I'm not familiar with conductive composites other than that I know they exist. I've dealt primarily with structural parts that did not require any particular conductive characteristics. I would think that a normal composite slapped on a steel barrel would work as an insulator and cook the liner.

 

[DT]

Thanks for the detailed reply. The one question I've been trying to figure out, but nobody has ever (to my knowledge) addressed in public is this:

Traditional aerospace composites have a matrix that is basically plastic, and poor heat conductor, that surrounds the carbon fibers. For example, when building a simple thin plate, you cannot reliably even get electrical conductivity from one side of the plate to the other. (I know, heat vs electrical is not exactly the same, but they go hand in hand).

And wound structures tend to be heavy on matrix relative to laminates (I was told that Proof barrels are wound?). What is Proof doing that mitigates this? Is it a specialized matrix? Some sort of trick? I'm not familiar with conductive composites other than that I know they exist. I've dealt primarily with structural parts that did not require any particular conductive characteristics. I would think that a normal composite slapped on a steel barrel would work as an insulator and cook the liner.

The matrix Proof uses is specialized to conduct heat. Testing at U of Nebraska labs found Proof barrel to cool more quickly that a stainless barrel of equal contour.

 

[jwing]

I have 2

7 and 6.5 both sub 1/4 to a 1000y plus.

Both hunting rifles, you can’t beat them for weight and ballance and accracey..
Yes there expensive but save on your hiking.

 

[Clancy]

I had Jon shoot a group or two after I had my proof installed, mostly because I was out of town and wouldn’t be able to shoot it.... anyway, these are the 4th, 5th and 6th rounds after zeroing my optic with the first 3. Not many #2 contours will do that.

 

[rhovee]

I have had a couple proofs. Big benifit is the ability to put a large break on the barrel. A #4 or 5 fluted is pretty similar in weight. Only thing I don’t like is the inletting for the stock. Once you have a rifle made for one hour kinda stuck. If you went with a Bartlein 3B then wanted to rebarrel with a Broughton #5 fluted then you wouldn’t need to do much. I am having a 300 Norma mag built right now. I decided to go with a #5 fluted and a Bat HR to have the ability down the road to change things up if wanted.

 

[alinwa]

Is it a specialized matrix? Some sort of trick? I'm not familiar with conductive composites other than that I know they exist. I've dealt primarily with structural parts that did not require any particular conductive characteristics. I would think that a normal composite slapped on a steel barrel would work as an insulator and cook the liner.

...... "other than that I know they exist. "

You SURE about that? You KNOW?? Or you've HEARD they exist......


LOL!!!!


Yer problem here is that you're applyin' REASON where feelings and beliefs is more appropriate........

I've been chasing this rabbit a long time. The first barrels were wrapped about 6 miles up the road from me. And I get asked a lot, my opinion. So I've asked a LOT of questions in the last 20yrs. As each maker steps up I try to contact them and ask questions as to "how" and "why" and "what"

with a variety of results.

I stood right there and lissened while one of the Good Ol' Boy owners of a composite coated barrel company ranted on as how "we DONE all those tests! We stuck a thermometer right on them barrels and we filmed them in infrared and we spot-checked 'em with them push-button thermometers and and them there carbon barrels heated up WAYYYY less! you shoot 20 shots and that there carbon barrel haitn't hardly heated up NONE!!! Them's FACTS ya' cain't argue with boy!!"

And he was right......It's just ridiculously hard for me to argue with that kinda' logic....... so I ditn't

And I was in the shop of another carbon barrel maker and he spoke frankly as how "wrapping a barrel is essentially like sticking the barrel in a sleeping bag".....

And I spoke personally on the phone with another maker who claims "heat radiates off the CF barrel like a corn cob! WAVES of heat! The thing is hot to the touch in just a couple shots!"

I've never worked with one that "radiates better than steel" altho some do radiate better than others (the mfgr of one in particular gave me a reasonable answer as to why....."we squeeze more of the binder out of ours") nor have I found one to shoot with an equal weight steel barrel.

Hey, lotsa' folks claim they make them shoot awesome, last forever and basically solve the problems inherent to barrels in general.

Lotsa' folks state baldly that "building 1/4moa rifles with CF wrapped barrels is easy, we do it all day"......... (altho I've yet to see a series of targets.....)

Well I don't,

I CAN'T

I do build 'em.... and I kinda' like the looks in certain situations, and I don't mind working on them, but I certainly HAVE NOT succeeded in making them shoot the way I require them to. I cannot sell them as quarter minute rifles.

I guess I'm just insufficient

Luckily there are plenty of folks out there to fill that pertickler niche in the market

 

[fredo]

The matrix Proof uses is specialized to conduct heat. Testing at U of Nebraska labs found Proof barrel to cool more quickly that a stainless barrel of equal contour.

Not a lab rat, but I'd like to peruse those test results, as well as get learned up on the methodology. Most obviously, where temp measurements were taken from each barrel. At the surface? Where at the surface? Inside the bore? Up inside a groove? On top a land? Would that test happen to be published in a journal somewhere, to reference?

Just wondering how a wrapped barrel can both heat up slower (stated above), AND cool more quickly (stated above), at the same time???

Course we all know that any test can be specifically designed to achieve a desired outcome. Beyond skimming a published test report, I'd be curious as to who paid for the test, and understand what scientific processes/controls were in place to insure objectivity/consistency in the testing process.

Not calling outright B.S., just seems that so much info around wrapped barrels is contradictory? Heck, we see it again here, in this very thread. So, who and what is one to believe?

Considering how fluting a steel barrel both decreases weight and increases surface area to expedite heat dissipation, I'd still like to know more about the 'magic' behind wrapped barrel that seemingly allows it to both heat & cool, faster OR slower, depending on what question the result is posed to address?

Somebody dun gotta gotta git learnt up on dem Laws Of Thermodynamics

Again, devil's advocate here...for the sake for clarity & understanding!

 

[DT]

http://www.shootingtimes.com/editorial/gunsmithing_st_carbonsnext_200901/100146

 

[Milo 2.0]

Again, devil's advocate here...for the sake for clarity & understanding!

I'm lost on the devil's advocate, IMO you are just adamantly opposed to a carbon wrapped barrel, for whatever reason.
In some instances they work, and work good, in others the application may not be there.
I would never even test drive a dodge truck, nevertheless entertain buying one, but people like them.

 

[3Ackleys]

this thread has a lot of great questions and observations. and here i am, chiming in again. no, i don't work at proof anymore.



good questions. i think they're a bit of a novelty and/or niche product. do they perform? absolutely, consider why. proof manufactures cut rifled barrels in house. christensen uses shilen barrels. they do not begin life as mass produced factory barrels. i do see ways that carbon outperforms steel, and ways that steel outperforms carbon. steel DOES get hotter faster (again, not sure about christensen), and groups open up. this is with ar and sporter profiles, by the way. match profiles may eliminate this advantage at the cost of weight. on the other hand steel IS stiffer, and is going to support a can better without drooping.

i've handled a 28" carbon fiber barreled rifle plus 2" brake and i honestly don't believe you can get 30" of all steel to feel that light outside of a pencil profile.



they definitely heat slower and cool faster. no asterisk there. i've seen test results where we ran steel and carbon shot for shot and measured accuracy and heat until the resin failed. i don't believe i should share specific results but the carbon barrel outperformed the steel barrel in that test and it was not close. until resin failure the carbon barrel kept accuracy much, much better than the steel barrel. it was a torture test with full auto mag dumps, mind you, so doesn't necessarily apply to bolt guns. it still offered a lot of information. carbon shrinks as it heats, unlike steel. this is not an insignificant factor as the barrel heats up.

now, as for the "risk of potential problems" comment, as a more complex component, yes. it's impossible for there to be fewer things to potentially go wrong. but for the most part, those issues have been satisfactorily addressed.



mixing carbon fiber and steel in a precision barrel definitely presents a large number of obstacles. many of those are overcome, and many you still have to deal with. it's not easy, which is why you don't have a lot of companies doing it. if you know the pros and cons of each, it definitely helps make a decision. i personally prefer steel, ONLY because weight is something i see as a positive. i wouldn't want a steel pencil, though, because the carbon fiber won't have an accuracy limit of 3 shots. now, for a hunting rifle, 3 shots may be 2 more than you need. usage makes a difference for sure.

I have a CA and a PR carbon barrel and have done load development for several more of each. All shoot very well.
CA says they make their barrels in house.
Brian Litz has a chapter in his new book Modern Advancements In Long Range Shooting Vol.II with a chapter comparing Proof and Christensen CF barrels to steel.
A couple of his findings ( there are 32 pages):

CF barrels cool more quickly than steel but also heat up faster.

Heavy steel barrels (m24 and hvy palma) are stiffer than CF.

POI shift during a 50 round slow fire test From the first 3-5shot groups to the last 3-5shot groups
Hvy palma .32 moa
CA Carbon .35 moa
M24 .45 moa
Hvy palma fluted .47 moa
Proof Carbon .88 moa
light palma 1.35 moa

 

[alinwa]

http://www.shootingtimes.com/editorial/gunsmithing_st_carbonsnext_200901/100146

At the risk of being perceived as panning 'Shooting Times' (LOL!! wouldn't want THAT!) my favoritist line from this article is this "
"Pitch fibers have a coefficient of thermal conductivity of over 700," Degerness said. "But the major challenge is that the higher the coefficient, the more it shrinks when heat is applied. As metal heats, it expands. You have to minimize this (in barrel manufacturing), or you will get a wandering point of impact. Getting the two to work together was tough"........................."You could shoot a .300 Win. Mag. five times, and the wrap would shrink 1/8 inch back from the muzzle nut,"

SO MUCH to pick on here!!! I love that conclusion that "the major challenge is that the higher the coefficient, the more it shrinks when heat is applied." I be love to GET ME SOME of that "shrinks when heated" stuff!

Here's an (admittedly insufficient but better than the ST article!) article which fairly clearly (and more importantly, FACTUALLY,) shows the cycles, clears up the "shrinks when heated" silliness. (For all you TLDR guys, think 'heat shrink tubing')

https://www.sciencedirect.com/topics/materials-science/carbon-fiber-production


jump ahead to "PAN-based" to save time

 

[alinwa]

I have a CA and a PR carbon barrel and have done load development for several more of each. All shoot very well.
CA says they make their barrels in house.
Brian Litz has a chapter in his new book Modern Advancements In Long Range Shooting Vol.II with a chapter comparing Proof and Christensen CF barrels to steel.
A couple of his findings ( there are 32 pages):

CF barrels cool more quickly than steel but also heat up faster.

Heavy steel barrels (m24 and hvy palma) are stiffer than CF.

POI shift during a 50 round slow fire test From the first 3-5shot groups to the last 3-5shot groups
Hvy palma .32 moa
CA Carbon .35 moa
M24 .45 moa
Hvy palma fluted .47 moa
Proof Carbon .88 moa
light palma 1.35 moa

OK, so I've argued with Brian wayy' too much to ask him this question directly but I'll ask all reading here...... "HITH!! was THIS "test" conducted???!!!"



POI shift during a 50 round slow fire test From the first 3-5shot groups to the last 3-5shot groups
Hvy palma .32 moa
CA Carbon .35 moa
M24 .45 moa
Hvy palma fluted .47 moa
Proof Carbon .88 moa
light palma 1.35 moa


I, me, do shoot some SERIOUSLY accurate stuff in a controlled environment (my own front yard) and I have NO FREAKING IDEA how to structure a test to illustrate "poi shift during slow fire"

Help a silly redneck out here eh???