They do move a bunch... rails and mounts are one of our focal points.
Gunsmithing Any thoughts on structured barrels?
- Thread starter TriggerJerk!
- Start date
Like I said-- you guys are the "why". Plus I just like problems...
Thanks
One issue I’m sure you’re all too familiar with but is worth mentioning for those that haven’t conducted an experiment. All too often has an experimenter set out to experiment just to find out there was something else going on. A lot of times it’s a good thing because it perpetuates scientific discovery and who doesn’t like to learn new things.
This is definitely a hierarchical problem because there are systems stacked on top of systems. I really wish I knew more about the physics because I did not know my scope was flexing like a trampoline lol
Most people here aren't saying structured barrels are "a bad thing" - but there's definitely questions around the cost/benefit. Structured barrels probably do provide some benefit - but to what quantifiable degree? They are really expensive compared to the standard alternative, so people are rightly asking what exact performance benefits they get and how much, by spending a large margin over standard barrels that give great precision/performance already.
It looks like you aren't using structured barrels either, so you probably fall in the same camp. Apparently a structured barrel isn't worth the performance increase for the price for you (my assumption) - and many here are doing the same calculus.
It's a pretty neat idea. I think many people see the ingenuity and potential benefits on paper. The real question is how much do those benefits translate to in real life? And are those benefits worth the substantial increase in price over a regular barrel, especially when barrels are such consumables?
I am no longer a Team USA Member but would be happy to put you in contact with the Captain. I guarantee if it works guys will use it. Right now Bartlein is the best there is. I have a trophy case of medals from Bartlein barrels. I am no longer that level of shooter so my testing would mean nothing
You keep saying a bencrest shooter or a PRS shooter is using them.
1 person out of thousands in each discipline is noise. And none of them are top shooters where equipment actually matters since they can out shoot it.
Kthomas makes a good point. No one is saying they are bad, or there is not the possibility of there being a benefit. Its the wild ass claims with no backup, no data and anecdotal examples that makes people extremely skeptical. I have shot 2 structured barrels for example. One shot well and one would not group for shit (using lapua brass, bergers, AMP, ATV3, AMP arbor press,ect.......the best equipment and components money can buy by an experienced and knowledgeable reloader). IMO, run of the mill traditional barrels that cost 1/3 shoot the same or better all things being equal. Which is why I want to test them, to prove this even though a sample size of 2 is not optimal.
When someone makes a bunch of claims, its on them to prove them. Show us the data, actually head to head comparisons accounting for variables so we can determine if its bullshit or not. If you want to sell barrels to people who actually know what the fuck they are doing, then you need to prove this. Until then, its snake oil being sold to ignorant people who buy into the bullshit and then are too embarrassed to admit they were fooled.
1 person out of thousands in each discipline is noise. And none of them are top shooters where equipment actually matters since they can out shoot it.
Kthomas makes a good point. No one is saying they are bad, or there is not the possibility of there being a benefit. Its the wild ass claims with no backup, no data and anecdotal examples that makes people extremely skeptical. I have shot 2 structured barrels for example. One shot well and one would not group for shit (using lapua brass, bergers, AMP, ATV3, AMP arbor press,ect.......the best equipment and components money can buy by an experienced and knowledgeable reloader). IMO, run of the mill traditional barrels that cost 1/3 shoot the same or better all things being equal. Which is why I want to test them, to prove this even though a sample size of 2 is not optimal.
When someone makes a bunch of claims, its on them to prove them. Show us the data, actually head to head comparisons accounting for variables so we can determine if its bullshit or not. If you want to sell barrels to people who actually know what the fuck they are doing, then you need to prove this. Until then, its snake oil being sold to ignorant people who buy into the bullshit and then are too embarrassed to admit they were fooled.
Easily one of the most annoying threads of 2020-2023, glad to see it's carrying over into 2024
What might help is if you can get some of those shooters to put pen to paper with a name.
Of course everyone will search immediately.
If the customer is a good/ reputable competitor opinions might change for the better
Just a idea
Edit auto correct again
All joking aside …how much nicer it this thread since a certain member isn’t here calling people derogatory names.
Still disagreeing but it’s civil
Still disagreeing but it’s civil
Absolutely- plus I am more than happy to use a Bartlein barrel as they have an excellent product.
I will happily put a barrel in their hands.
We don't improve upon the base barrel "per say". Are goal is to allow it to function at higher sustainable values than its base design can. Kind of like optical elevation adders. They don't improve the scope but now the scope can be used well beyond its design criteria. We can't improve Bartlein's one hole performance- but if we can remove some random fliers, extend shot strings through a cooler system, allow a shooter to stay on target due to less barrel whip... we are gaining something.
As the 1000yd bencher said- " I don't care about individual matches, I care about the aggregate for the season and its performance overall". Several 1st places certainly help in that arena.
Gleaning small percentage gains in a tight field is called "time" for us.
Competition results aren’t proof of a better product. Plenty of people win competitions with a Vortex or Burris optic, doesn’t mean it’s a better optic than a ZCO or Tangent.
All tacom needed to do was say “we offer the same benefits as a CF barrel (lower weight for same stiffness) without the downside of delamination” and this thread wouldn’t have happened. Instead, they start writing checks their ass can’t cash:
•lower SD
•longer barrel life
•lower recoil
•magical load development using 1 shot per powder charge that defies basic statistics
And like a dozen other things
Add to it John Baker’s inability to 1) provide proof of any aforementioned benefit over equal quality normal barrels and 2) explain it without sounding like he’s in a Rockwell Automations advertisement. It’s stereotypical used car salesman, just like Erik Cortina saying “tuners work but we just can’t tell you how to make it work”.
Do structured barrels have an advantage? Maybe (if they’re made consistently enough), but then there should be more than a mormon couple of shooters using them.
All tacom needed to do was say “we offer the same benefits as a CF barrel (lower weight for same stiffness) without the downside of delamination” and this thread wouldn’t have happened. Instead, they start writing checks their ass can’t cash:
•lower SD
•longer barrel life
•lower recoil
•magical load development using 1 shot per powder charge that defies basic statistics
And like a dozen other things
Add to it John Baker’s inability to 1) provide proof of any aforementioned benefit over equal quality normal barrels and 2) explain it without sounding like he’s in a Rockwell Automations advertisement. It’s stereotypical used car salesman, just like Erik Cortina saying “tuners work but we just can’t tell you how to make it work”.
Do structured barrels have an advantage? Maybe (if they’re made consistently enough), but then there should be more than a mormon couple of shooters using them.
You are absolutely right about the cost. ELR barrels are literally one of a kind one-offs every time. We hope to move towards AR10 barrels which will allow for a standardization that cannot be applied now. Individual shipping costs are substantial by themselves. We/TACOMHQ has to determine if a market exists. At one time a Douglas premium barrel was how much? Now Krieger and Bartlein? Premium materials? Exotic processes? Some might consider the extra cost to chamber a barrel and muzzle work to be part of the equation and or load work up. We have chamber jobs at $800+. I would also assume a cut rifled barrel start up is substantial.
I will be interested in seeing other 30-40 round groups that we are being compared to. We all need to understand the playing field.
Drew- I believe you are telling me to ignore my customers findings.
Again- there is no "proof" I could provide to someone like yourself. It does not exists.
I believe you are a person who would "throw a game"- ie... ruin one of our barrels just to be right.
Is that good or bad?
So all your customers are right and anyone who is skeptical is automatically a bad actor who lie/cheat?
If I was you i would delete all my posts and stop posting on social media. Its going to be harder to fool people into buying the snake oil when they do google searches and this thread pops up. I will continue to call it snake oil until you accept my challenge or provide data that shows a reasonable correlation to the claims you have made.
If I was you i would delete all my posts and stop posting on social media. Its going to be harder to fool people into buying the snake oil when they do google searches and this thread pops up. I will continue to call it snake oil until you accept my challenge or provide data that shows a reasonable correlation to the claims you have made.
Or… you could provide actually peer reviewed 3rd party data from a reputable source - not someone advertising your products (cough cough coastal precision)
John is advocating super rigid which is great meaning any bullet shoots same poi same tune at one hundred yards and does not go out of tune by reducing if not eliminating the negative or downward bending of the barrel. The only reason I am not using his barrels is I need lots of bending for positive compensation and am tuned for only one bullet at any velocity..so I am doing it from a different angle. Both ways can shoot well at all distances as evidenced by Chris Schmitt's world record and with a cold bore 3 for 3 at 2800+ Chris can keep his ES good so the rigid Barrel is parallel during all exit times with any bullet and any speed. Try going and shooting two or three different good quality bullets noting POI change there will most likely be a change which means your barrel is bending. Even with big velocity between bullets they should only drop a few thousands of an inch , If it is more than that than your barrel is bending and if it is you better at least control it.
Rounds 21-30
300 Norma, 208gr, 58deg, 34.7%RH, barrel could be picked up by hand at the end of the string... temp 110deg. 18min for 30rounds. Tubb Gun, Tangent Theta.
@John Baker
Having small issue with the website on my end. What would be the lead time for a 6mm and .308 barrel around 26" with whatever contour you'd recommend for best performance?
One would be for an AXSR (so I'd have to see what max size will fit in hand guard) and the other would be a PRS type rifle. Likely in a foundation.
Thanks
Having small issue with the website on my end. What would be the lead time for a 6mm and .308 barrel around 26" with whatever contour you'd recommend for best performance?
One would be for an AXSR (so I'd have to see what max size will fit in hand guard) and the other would be a PRS type rifle. Likely in a foundation.
Thanks
Rounds 31-40 6xc Tubb Gun, factory ammo (2007LOL), Vortex GenIII (like that scope), 48deg, 84deg barrel temp after 43 rounds, 20min shoot time, bipod and rear bag. I know the gun can do better... RL26 6xc was shooting better right up till the scope went poof...(Not the Vortex...)
Let's talk- who would be your preferred blank? That is the big lead time setter. Each of the major caliber groups have an optimum design for stiffness and surface area for cooling. Let's talk about that and see how it fits your needs. Fitting the hand guard- sometimes easy sometimes not so easy... part of it is the furniture requirements that take up the interior space.
I think a 1.35” is max. That’s what I recall when I bought a couple barrels for mine.
My favorite fact data guy LOL. You kind of "hush" the world.
We have:
2 MRADS, 3 customs, one custom using off shelf components bolt together. All 300Norma. One of the customs was produced by a well known shop. One is my old stand buy Norma with well north of 1500 rounds on it. I could probably retrieve our modified MRAD that has our barrel. Making 4-6guns side by side.
My base starting point for a test is 30rds each. 100yds. Time limit.
230gr Norma Factory Ammo.
How would you round robbin a test?
I do not have 6 matching scopes.
Perhaps we could get a scope group to step up..
1 scope in a quality quick change mount? You are caring more about the precision than the accuracy so not having a perfect zero isn't as big a factor.
Excellent thought. Checking for a 34mm and 35mm tomorrow.
just to confirm, and you have had ample opportunity, you have zero published data to support the wild claims on your website? I think that's pretty much all we need to know here. Thank you for coming here and telling us all what we had long known.
If we can agree the barrel is the central force (not arguing when as compared to immediate ignition) that starts the whipping action as seen in multiple videos... and our barrel is stiffer... would it stand to reason that less whipping occurs at the scope. We have excellent videos of a .460 and .416 in recoil. I need to dig up the videos of an ELR .416 - one with and one without. Barrel whip... of course, video evidence is objective, circumstantial, not peered reviewed, anecdotal nothing, that will never be accepted by some.
Plus if we want to argue the point that a solid rod of the same weight as a tube (let alone tubes) is stronger... then ignore this unsubstantiated claim. Solid Rods.. tube.. HS physics... its always been wrong.
Hierarchical problems- 90% failures imbedded with 80% failure modes and keep on ticking them off. Many with the same outcome. Taking a "guess in the dark" action to see a result in order to get base lines of various magnitudes and order of occurrence.
Ok..
I have been challenged to produce 30rd groups.
Compare multiple rifles side by side.
What is published data? what is the form? what is an example? Please supply other published data for other products so we have an outline to follow.
What is "peer" review? When every one of my sources are considered morons.
If 3rd party extended string groups of various ammo is not a "peer" review what is?
Would JB.IC be adequate as a tester and for peer review?
all good questions to ask and things to consider before you put the claims on your website. How did you verify said claims if you cannot offer us any proof??
Here is what real manufacturer's testing looks like: https://thunderbeastarms.com/sound/summit2023/
I would assume that if the barrel perpetuates or even magnifies the whipping forces then a barrel that reduces those forces would also reduce any perpetuation or magnification. That’s actually something worth exploring. ELR, for instance, is harder in say accuracy and precision not just because of the distances but because the monstrous cartridges.
Let me think about the experimental design. I’d like to run some simulations to get an idea. I’m assuming for this particular experiment, group size is the response variable. If we want to estimate the experimental error, then we will need more than one group. We need to think about what to consider a practical difference. Is a mean group size difference of say 0.1, 0.2, etc. between unstructured and structured practical? Basically, what are we calling a practical difference which will help with estimations.
I like the idea of putting the MRADs against each other because ideally, they will have the least differences in rifle characteristics. Obviously, that won’t generalize to other rifles which can be good or bad. Test like these are hard to generalize if there isn’t a ton of money to throw at the research. But nonetheless, something can be learned and estimated and that’s valuable.
This post, among others you've made, makes me question if you understand the physics of the firing event.
The breech load is the central force, the projectile loads are small in comparison. Lateral barrel motion is driven primarily by an offset of the gun CG from the center of the breech face and secondarily by asymmetries in receiver stiffness.
This data does exist, using both eddy current sensors and laser vibrometers. It shows small amounts of movement, and variation in that movement does affect dispersion. I suspect a clever arrangement of sufficiently sensitive strain gages could also work, but would leave out the rigid body motion that occurs.
That's not the premise being proposed, but even if it was, the powder column is still acting on the barrel. The removal of the projectile does not imply the removal of all forces. Beyond that, the fact that the barrel movement is larger after bullet exit than before is easily observable. As you yourself have pointed out, current high speed cameras are not capable of resolving the lateral movement during barrel time, yet there are many videos showing movement after bullet exit. The obvious conclusion is that the barrel is now moving enough to be within the resolution of the camera.
I think you're strawmanning here (no one thinks that the barrel has no effect), but some of those questions are interesting regardless.
1) Troll question - barrels obviously change with shot count
2) Depends on the type of degradation. If you agree with Litz that the first sign of a barrel going out is BC variability then you will see vertical spread increase first. Opening of the entire cone of dispersion will come later.
3) Probably not, small changes in powder charge are unlikely to cause a large change in obturation.
4) Depends on the line, but yes. Any change in projectile mass balance will have negative effects. Scribed lines with radial symmetry won't have this effect.
5) See 4)
6) Yes, provided nothing in the gun has changed either.
7) More mass more better (unless you have to carry it for long distances, also notice I didn't say stiffness)
8) If you aren't just being snarky, there's a pretty clear explanation as to why the group is opening in all directions. Two of the largest contributors to dispersion are lateral throwoff and aero jump. Both are influenced by asymmetric engraving and in-bore yaw. As a bore expands, the amount of yaw possible increases, but the direction in which it occurs is random. This results in a increase in the entire cone.
9) Not worded clearly enough to answer. Same strawman about barrel not having any influence.
10) See 8)
It should be measurable and predictable, but it's not. A person could make a killing in the custom barrel market if you could tell a good from a bad barrel simply by inspection. This excludes things like comparing a barrel at SAAMI max bore and groove vs one at min, the outcome there is at least somewhat predictable.
Yes, but that's nothing to do with harmonics.
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Day 2- same 300Norma Tubb Gun. Rounds 21-30. 208gr at 3164fps. 1800+ rounds on the barrel.
I would suggest you look at Harold Vaughn’s book rifle accuracy facts where he put sensors in a circle around the lug and used compression forces as a reference of how the barrel was moving . That has already been done . And shows patterns very similar to my target graphs . Even if you can measure these movements at the muzzle which is all that matters , you have to relate a particular measurement or bending to the target which makes it literally impossible to do with any credence due to so many other factors that you yourself have stated . Why do you think it has not been done yet ? Could be random dispersion not related to the barrel bending . You must be able to distinguish which and ladder tests do that . So back to my original claim which is ladder testing is the only way to measure these movements . There is no other way without modifying the barrel movement which I can say without a doubt can be changed by the slightest offset with a sensor even if it is only a few tenths of a ounce. Laser , spark , or any other sensors just will not work. I am open to any ideas but right now nothing you have stated will show where the barrel is aiming the bullets and which movement is responsible for that particular point of impact without changing the sensor free movement .
I've read Vaughn's book multiple times. His approach was impressive for the time and the technology available, but measuring only receiver moment gives very limited information. There are effectively infinitely many deformed barrel configurations that can produce the same moment. His addition of the muzzle accelerometer adds another data point, but is still insufficient to derive an accurate pointing angle.
I've posted about this before, so we'll try again. This has already been done in the Army Research Lab spark range, with both eddy current sensors and laser vibrometers (obviously both non-contact). It works, it's been published. Their setup allows measurement/calculation of all jump components (pointing angle, crossing velocity, aero jump, and CG jump).
ETA: I really hope you aren't implying that a laser shining on the surface of the barrel will affect its motion....
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No , what I am implying is that any movement can be measured but can not absolutely be related to the POI. Remember if it is not physically connected to the gun there are many movements , rearward , torque ,and muzzle rise that will skew the measurement . Edited if the rifle is in a fixture restricting the gun in any way the barrel movement is effectively changed reducing the bending and completely changing the dynamic response as well .
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You are correct in 100% hindsight. We assumed the community would accept 3rd party information - Coastal Precision, Mark and Sam Afterwork, various shooters. Horrible assumption. Using their findings as "potential" advantages was a mistake.
I never dreamed that users of a product would all be called morons.
Updating web page components never occurs anywhere else as information and public acceptance is further reviewed.
We are removing all references EXCEPT for:
Stiffer Barrel for its weight
Reduced Mirage
Lower Heat content.
You are also correct- the testing by Thunder Beast Arms was outstanding. I am sure their first postings had this depth of format (No attack on Thunder Beast Arms). Something I am sure all small shops start with. Hence using the public users for data. How many start up companies produce such data? I am sure you could research other large corporations and find research (content volume) that will dwarf theirs too. What I am saying is "scale". Noting we are not a "real manufacturer" ... choice words.
I don't see any reason why a test couldn't be devised that would relate barrel movement to POI.
A simple ladder test cannot do what you are asking it to do. There are way too many variables that are uncontrolled and unaccounted for, in order to make these types of conclusions.
Yet here I am , using ladder tests to see untethered effecting barrel movements , lateral velocity , amplitude , and launch angles to a precise degree and confirming it out to two miles or farther down range. . If lasers are used the gun must be in a fixture to prevent over all movement . Otherwise you are measuring the bending of a fixture and it’s effect on the gun nothing more .
You're certainly doing something, alright.
I'm just not convinced that your testing methods can give the dispositive conclusions that you claim. But that's for a different thread.
Does that mean that a “tuned” rifle will go “out of tune” if you shoot off a barricade because it was “tuned” on a cement bench free recoil?
No that just means you stacked or added some more variables in to that shot lol. Do you test offhand ? I sure as hell don’t.
Testing aside, question was the different situations cause the rifle to go out of tune?
No
I think we have a definitional problem here. Knowing the total jump means that all contributions to the delta between initial boresight and point-of-impact are known. Muzzle rise is a component of pointing angle that is already being measured, rearward movement can be measured, and torque can be measured but does not change the pointing angle or cross velocity.
The location and total yaw of the projectile is known at every point between the muzzle and the target. The gun is in a fixture with a recoil buffer, which will change the dynamics of the barrel to some extent relative to shoulder fire. The people running these tests aren't stupid, one of the publications directly covers the use of the setup to assess the influence of different mounting methods on barrel motion.
I understand not saying it is not right .If they were testing my gun and they did it that way , I would still be worried . I could be wrong no doubt but would feel better if the same test was ran shoulder fired on bags and then compare results between the two as a confirmation. The reason is over the years the overall dynamic is soooo sensitive to change it is scary so I would like to confirm my testing with the same support just to make sure I am not sunk just because the gun reacted differently. For example I would have never thought a wood bench would change the gun but it did and stopped putting slower rounds high and this was a really sturdy bench but wood. Walked over to a concrete bench to shoot off of and life was good again .
