Perhaps for a specfic caliber or cartridge or specfic platform or specfic conture. Yes
- Thread starter badassgunworks
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Alex, A heavy weight on the muzzle can increase accuracy and it can decrease accuracy ,but does not necessarily create less amplitude, sometimes it can increase the amplitude ,I am referring to weight in front of the muzzle. The weight behind the muzzle leverages the muzzle differently. The weighting in front of the muzzle is delaying a reaction at the muzzle so the angular bending which naturally wants to bend down when the rifle assembly bows up in the middle. Lets address some of the things you mention but I am primarily speaking of the modes that will effect poi and after ignition and before the bullet exits. Anywhere from .9 MS to 1.8 MS. You mention harmonic bending with frequency. I agree there is no single plane in High frequency vibration which is the vibrational mode driven by the case slapping the chamber wall and bolt lock and pressurization upon firing. This is a powerful transverse wave that will hit the muzzle approximately 7-8 times before the bullet exits. If the high frequency is at the muzzle upon the bullets exit it will create a random dispersion , I have found this to be true upon testing a specific powder charge the groups will open up excessively in a random dispersion pattern. If this high frequency is at the muzzle when the bullet exits then the bullet can actually carry some of this high frequency with it causing some slight instability with it but the primary effecting factor was the muzzles extremely high cross tracking velocity created from the high frequency. This effect was also noted with 16 inch naval guns in a white paper report I had read from a Navy lab. The fix was to simply change exit timing or velocity. On a rifle this would mean a change of .5 grain on a 300 Win Mag would change the exit timing enough to exit at a time with a stable muzzle and with a much slower cross tracking velocity , so there is a window of exit time that the HF will not be there so then that mode is completely non effecting on the poi. As to the second mode which is the forced deformation driven by the recoil force combined with the weight offset of the rifle. if the stock weighs 5 lbs and the scope and mounting weighs 2.5 lbs then the amplitude of the bending will be enough to see it bending around the heavy side. it will bend around the heavier weight bolted to the barrel action assembly. This mode is vertically oriented foregoing torque as a very small factor in the horizontal and does not have a frequency necessarily , sometimes it resembles a frequency but other times it is erratic from one movement to the next depending on the weight . This is the movement that a tuner will correct or make worse and is why it is vertically oriented. Here is graph showing a very wide window of the vertical movements showing poi change which is a direct trace of the barrels movement though various exit times. This was under highly controlled conditions. A weight change of only 1.25 ounces changed the pattern noticeably smoothing out the movements . The cross tracking velocity of the muzzle is very slow while moving up [gun shoots well] but when the muzzle is moving down the cross tracking velocity is about 5 times faster affecting the bullets stability as well. so reducing the downswing is good , certain weighting can also tune in a parallel muzzle pattern if desired even with thin barrels. A adjustable weight will speed up the pattern by moving the adjustable weight rearward and forward to slow down the movement relative to the exit time of that bullet. The weighting 3-8 inches behind the muzzle I would suspect will have much less of a effect but I have not tried it. This graph is the only way to accurately measure movements of the muzzle as of now but if you can do it with piezo sensors and relate it to the target it would be interesting to try it.
timintx
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do you speculate that muzzle weight is shrinking vertical dispersion,
or it shrink dispersion in every direction because of high frequency vibration, so it will shrink whole group?
or it shrink dispersion in every direction because of high frequency vibration, so it will shrink whole group?
Both . I have not measured the specific amount of reduction but bear in mind the high frequency is only at the muzzle at one particular exit time within the whole loading range of powder charges , so if the groups are excessively large to begin with then the weight would help , but not eliminate the dispersion . The only way to know if it is in fact HF at the muzzle is to change the powder charge a bit to confirm , if the groups are considerably smaller upon the powder charge change ,then go back to the bad powder weight then add weight to gauge the amount of reduction .
timintx
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I actually did say reduces amplitude. I don't see a physics mechanism that would cause it to increase amplitude other than chance constructive interference by causing different harmonics to overlap. Even then, the additional mass would probably overcome even that.
You mentioned having the weight backed off the muzzle. I saw a 50 caliber gun with the tuning weight that simply clamped down on a bull barrel with 4 bolts. In one case the guy had it about a foot and a half from the muzzle to get the desired effect. Again, this was a weight that looked to be a few pounds of steel. Heavier barrel is going to take more of a change in mass distribution to alter the harmonics that a pencil barrel.
Can you show error bars on your graph?
Measuring with piezo is a logical approach for an approximation. Wouldn't give you directional data though. It would be a much more expensive set up but having lasers measure lateral movement from the bottom and side would let you extrapolate movement in 2 dimensions. Might be possible with reference dots and a high speed camera too. Would be interesting to correlate bullet dispersion downrange with the position of the muzzle when the bullet exits.
-Alex
Sorry I said it wrong , I flipped the words around wrong ,the point was it can increase amplitude not just reduce it . This has to do with positioning of the weighting . Not sure what you mean by error bars . The gun was extremely accurate in loads and barrel though . And conditions were highly controlled . Yes lasers could possibly measure but you have to separate the various movements and relate them to the target which is a tough one to do . No military labs could do it . But I am still looking for a way to do it .
timintx
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Coefficient of Inbreeding?
In any data set where you have a bunch of measurements that you average together, you can also kick out SD and generate the CI for that data point. Think of it as the visual equivalent of a T-test.
-Alex
The pressure wave propagates back and forth down the barrel at 17 times the speed of sound enlarging the diameter of the barrel wherever it is at. The most accurate position is when the wave is near the chamber, the least accurate position is when it is near the muzzle.
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after 10y of looking at OBT and other hypothesys, it's time to say that this does not translate to rifle precision.
Your correct just accuracy. The one thing that most so called precision shooters lack.
0.001401869158879 of a second.
Appreciate the fast response, I’m just a humble rimfire shooter with 1070 fps ammo in a 1.5ft bore, trying for small groups at 300-500yds.
Following your discussion, and the search for reasons why a tuner works, I first think someone needs ultra high speed footage of a muzzle being tracked in all its axis of movement through the firing cycle, and that correlation to accuracy or inaccuracies.
Some explain that barrels move in a whip or sine wave through the firing cycle. Ok. What factors cause this? The barrel drooping from gravity and suddenly snapped upwards like a noodle balloon taking a puff of air, due to the firing gas pressures involved?
What effect does inertia play?
What effect does torsion forces play(after all, the rifling is imparting a rotation to the slug)?
Would a smooth bore barrel behave the same way and respond to a tuner the same?
What about a bore with straight rifling?
What part does a tuners inertia play? Does an 11oz tuner that is 2” long perform the same as one 2” in diameter?
Assuming the barrel moves rearward during recoil, and our theoretical gun has a buttplate who’s center is at boreline, what effect does the inertia of the stock and scope have on the bores recoil track and thus yet another Exterior force on the barrel?
What can mitigate the tuning fork effect of the harmonic between barrel and scope?
During firing there are several signals sent down the barrel’s steel, the sear break, trigger slapping it’s stop, firing pin striking primer (and firing pin spring resonance), case surging into the chamber if there is play/then the pop of primer, etc. etc. etc.
Does this vibration timing effect muzzle location? What about electric ignition, would it be better/reduce variables?
The bore expands and contracts as the slug passes due to the low pressure in front and high pressure behind the projectile (or so I’ve been told), what effect does this have on said resonance/frequency/amplitude?
Instead of tuning or amplifying what’s going on (is tuning changing the frequency, ie. Tone?) what about deadening?
Would an acoustically dead barrel give the best accuracy of all?
thats the real problem..money
lots of money and limited ROI
spend money and the idea doesnt work as well as expected...loss
spend money and the idea kind of works...loss
spend money and the idea works...possible ROI for believers
spend money on a mechanical accessory that isnt special (because there is nothing "non electronic" that cannot be advanced once the original is on the market)...thats just manufacturing.
shooters still need to read the environmentals and adjust, a rifle that shoots .1" tighter groups will never out shoot someone who can read the environmentals better
Think of it like a chassis, the first chassis were special because they were new
and really the chassis that started the craze was the AICS, and thats only because it looked really cool (thats why i bought one years ago) and because the actual OEM rifle was more expensive than almost anything else out at the time
now everyone with a lathe has a new chassis coming out every 6 months
rifles arent special, its a pipe screwed to a pipe screwed to a piece of wood or metal and then a trigger is screwed to that
buy a bunch of "high quality pipes" and you have a accurate rifle
which is why its not just one smith, or mfg is winning everything or holding all the records
The vast majority of people wouldn't know how to test it - let alone have the time or resources to do so.
That's why so many shooters and reloaders draw conclusions (that don't actually exist) from insignificant sample sizes. It's why people think they can use the "Satterlee method" to find a load. Or 3 round groups to find the best seating depth. Or 2 round groups to find the best tuner setting. Or a 3 to 5-shot string over a chronograph to capture your loads ES/SD (nevermind that you had to shoot it 20 times to get that perfect 3 ES string to post on FB for your followers to jerk off to).
As humans we are biased towards remembering the best results, while forgetting the bad to mediocre results. It's why we think we all have 1/4 moa or better rifles, even though it takes numerous groups to produce that result. Or why we think our reloads have better ES/SD than they truly do. If we extrapolated out our results over a much bigger sample size, our results would not be near as good as our bias would have us believe (and that's not even getting into our compromised testing methods).
However I do wish people would test more stuff - but just be mindful of the limitations. A lot of my own testing with much larger sample sizes has invalidated my previous conclusions that came from much smaller sample sizes.
this is all 100% true.
BUT...
it's hard to spend all your barrel life for testing the best load for 50 shot groups...
so it is very important, that we realy find what drives our rifles to better precision. maybe bryan litz will discover this topic, maybe he wont. but clearly nobody cant spend his whole barrel life to test with 50 shots what seating depth is the best in 0.005' increments, what powder charge is the best in 0.3gr increments, which primer is the best, which bullet is the best... too much variabiles and no time to do it all.
we must find something more efficient, or we have no choice than run only 5-10 shot groups and prey for objective result...
imho.
Exactly.
No individual is going to do that kind of testing, myself included. That's why you should take any anecdotal evidence on the subject with a heavy grain of salt.
It's also very difficult to isolate all the variables, there's always going to be numerous variables at play no matter what you are testing. Which makes things even more difficult to ascertain.
I've spent most of my current 6BRA's barrel life testing things for myself. By no means definitive. But I've found that a lot of things simply don't matter as much as we think they do, especially for the kind of shooting the vast majority of us on this site do. Things that may seem certain or conclusive in small sample sizes simply don't flush out at all with larger sample sizes - I've seen this through my own testing with seating depths, powder charges and tuners for example.
But thankfully all the testing I've done has resulted in more simplicity for me in my shooting. I don't need a tuner to have a very precise rifle. I don't need a specific powder charge to have very low ES/SD's. I don't need to chase the lands with my bullet seating depths. I don't need to clean and uniform primer pockets, etc. There's a lot of noise when it comes to the topic of tuners and reloading - but very little substance in a lot of cases, IMO.
Anyways, back to the productive conversation that is this thread....
problem is that the last few posts are the productive posts
without verified data the rest is just internet posting while on the shitter lol
Lol, agreed.
But we shouldn't expect much when the thread started with "X shooter won using this equipment, therefor this is irrefutable proof that this equipment works".
Not a very compelling or informative opening to a discussion...
The post served its purpose. The point of the post was we have one guy who did a shitty test to prove that they don't work. For monetary gain. Then you have the entire industry using them for 25 plus years that was the point of the post
I shoot F class (FTR) and was paired with a very well know F open shooter that often sets national records. At a state championship match I watched him shoot 3-4 sighters at 1,000 yards. Couple 10's here and there and X. Watched him twist the tuner and hammer X's for score.
Bought one for the next season and have been playing with one. I have seen some significant changes both positive and negative. My take is you have to spend some time to figure out what "your barrel" likes.
Hope to shoot match in spring after more testing.
Bought one for the next season and have been playing with one. I have seen some significant changes both positive and negative. My take is you have to spend some time to figure out what "your barrel" likes.
Hope to shoot match in spring after more testing.
I think what you said is what’s good and what’s bad about tuners, or what is known so far.
Like Lou Murdica who uses a tuner on some rifles to squeeze the last drop out.
But the gear, load, shooter skill have to be so “perfect” that regular people will not be able to extract the difference.
So one set of data will show it works and the other data will not.
What we need to know is how your friend knew which way to “turn” the tuner and did he expect to adjust that day.
yes it does work .i to have a EC Tuner break . to get a better price wait till black Friday to order
The negative aspects of a tuner is no different than the negative aspects of reloading. Person who is just learning how to reload has a huge learning curve it is no different than using a tuner. Environmental changes and throat wear have a dictated results on your group sizes. Being familiar with your tuner and what it does is absolutely no different. As your throat wears pressure drops. As temperature changes pressure changes. The direction you turn your tuner is irrelevant as the results were repeated if you have enough travel. A quicker response is determined by the direction that you turn it. As the changes happened to the platform our gradual therefore the amount of changes to the tuner is subtle and small in increments. Thread tpi weight and location of tuner in relation to crown has a direct effect in how responsive your tuner is. Some of the tuner manufacturers are not going to like my next statement. All tuners or I should say most tuners do work as to how rapid the response is is hit and miss. The reason for this is that you cannot produce a generic tuner and have it be optimized on any and all platforms. A optimize the tuner must be built rifle specific
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exactly
the tuner market is a one size fits all solution, which in theory is possible
but the ability to manipulate vibrations and movement accurately and repeatable is much more complicated
There's a lot of snake oil around the current crop of tuner salesmen and "enthusiasts".
I'm extremely skeptical of the following claims made by tuners being sold to the PRS/"practical" disciplines, especially given the lack of any compelling evidence:
- That tuners will make your reloads more precise
- That tuners will make factory ammo more precise
- That tuners can be used to skip the load development process
- That you can find the optimum tuner setting or "node" with just 2 round groups
For the record, I don't think @badassgunworks is one of these snake oil salesmen. There very well could be something to tuners if used for the right application and properly. I don't doubt the success of tuners in BR and F-class (in which they are used in a much different application than tuners are proposed for here on SH). A tuner specifically made for a rifle and load, used in the proper application (such as how they are used in BR and F-class), seems much more reasonable than what is usually proposed on here.
There's a big push to sell tuners with the snake oil that they will shorten the load development process, make your reloads or factory ammo more precise, and all you have to do is shoot some 2-shot groups to find the "node" and you are set. That's a bunch of BS. I'm more open to the idea of tuners being used in a much more specific and optimized manner, one in which they are actually used for in other disciplines.
The only thing IMO would be possibly having a log of shooting in similar environmental and having a few tuner settings that seemed to work that day and going in and around those until you think it's grouping well. Or literally just tune it during sighters which might take a bit
thats my thoughts as well
which leads me down the path that tuners arent easy / for beginners, they may work but tons of snake oil
its for shooters who are 100% fully in tune with their rifle and that keep meticulous records etc
which is along the lines of what @kthomas just posted
thanks
Alex Wheeler, a world class shooter and BR gunsmith (built many rifles that have set records in that discipline), tells his clients to at least shoot out a barrel or two in competition before even thinking about adding a tuner to the equation.
Because tuners are not the "easy button" many sell them as.
Biggest problem PRS is anything but precision. Many people confuse Precision with accuracy. I can tell you this much and 28 years of being a I am Guild grade gunsmith and many years of competing in bench rest I have seen some rifles that just would not group well no matter what you did no matter how much time you spent developing loads trying different seating depths different neck tensions different powders and volumes just wouldn't shoot well or there was no Rhyme or Reason for the results and a few of those cases where I installed a quick built tuner was able to get them to shoot much better. However it would not turn a shitty gun into a competition quality build many of those rifles were custom built ultralight pencil Barrel fluted Mountain guns. And most of those cases a tuner did a world of good and a lot of it what's the extra weight that was added to the muzzle
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Exactly.
I don't shoot for a hit on steel, I shoot for a score. Big difference between a bunch of 9's and bunch of 10's and X's.
Load has already been dialed in and done well. However, I'm going to play with one for some time before I use one in a match.
1000% “shooting steel” ruined true precision.
tuners work, but how is the real quesiton?
and the answer to this question will give people who test a LOT. realy A LOT. and I know only 2 of them, who effortlessly test and share their big data to us, and that's are bryan litz (who sell his findings) and LEDZEP here, who test 20+ samples to see real statistical proof, and not 2-shot-bullshit-turn-your-tuner-1/32 and look for round 2-shot groups and this statistical retardness of ALL those tuner sellers!
only with people like this, who test big sample and see what is bullshit, we will realy find what works and what does not.
because those can prove that statements like ''0.003' stating depth make difference'' and ''0.1gr powder charge best precision window'' are the most retarded and harm shooting and reloading comunity because they sell their snake oil gears with lies.
and this all goes for 1/360° turn tuners, primer seating depth, 0.001gr precise powder charges, mandrells, annealing and other magic stuff...
Yep. Tuners are not some "magic snake oil".
Yep, equal to knowing your load, how your proj like to jump, and how sensitive your powder is to DA / temp. You must know them intimately.
Hah also true. Its why i have multiple size and weight tuners.
You hqve different size tyres for cars. There is (almost) no "one size fits all". Cartridge, barrel contour, barrel length, etc..
Now ill throw a spanner in the works. Do barrett rifles bed the WHOLE thing ? Not just the receiver ? Id be curious to see how that works. Ive never bedded a whole barrel channel before.
Look on the video of Bryans gun with a match stick which shows clearly the muzzle is moving down as it moves rearward . if you are not sure, lay a marker on the screen to see it and you will see a drop in muzzle as it moves backward before the bullet exits. It does not mean all guns do this though.
timintx
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Valid points all the more of a reason to have a rifle that is built center of gravity and built for proper tracking witch most elr rifles are not. Also having a tuner brake that it designed to eliminate muzzle jump
Wanna do maths ? Lets do some maths.
You have a 1moa gun, and get a single flier which opens it to 2moa.
1moa = 0.01667degrees.
Draw a right angle triangle. With 25.4mm vertical, 100m long horizontal line. The tiny angle is 0.01667degrees.
Now draw a triangle where the long side is 26" (660mm long) which represents your barrel length. And we know the angle of deflection to get a 1moa increase in flier is 0.01667degrees. thr muzzle must deflect 0.19202mm, or 0.0075598".
Human hair is anywhere from 50 to 120micron, so say 70micron average (wikipedia) which is 0.07mm.
Muzzle deflection of just over 2.5 human hairs is 1moa at 100m.
Or simply 2.5 franks in muzzle movement is 1moa accuracy.
Lets see your slow motion camera detect that.
You have a 1moa gun, and get a single flier which opens it to 2moa.
1moa = 0.01667degrees.
Draw a right angle triangle. With 25.4mm vertical, 100m long horizontal line. The tiny angle is 0.01667degrees.
Now draw a triangle where the long side is 26" (660mm long) which represents your barrel length. And we know the angle of deflection to get a 1moa increase in flier is 0.01667degrees. thr muzzle must deflect 0.19202mm, or 0.0075598".
Human hair is anywhere from 50 to 120micron, so say 70micron average (wikipedia) which is 0.07mm.
Muzzle deflection of just over 2.5 human hairs is 1moa at 100m.
Or simply 2.5 franks in muzzle movement is 1moa accuracy.
Lets see your slow motion camera detect that.
uhhh, tuner producers, 2 or 3-shot vibration gurus, flat spot seekers, velocity platoes finders, primer seating depth advocates and other snake oil sellers won't like this...
Set up as shown in the Instagram video, you're not going to be able to measure a 175 micron up/down deflection accurately. And as Litz mentions, the recoil movement is significant. But, with a better setup - a sharp point attached to the barrel backed by a calibrated grid with 10 micron line separations, a higher lens magnification, etc., would allow you to do far better. You'd need one camera set perpendicular to the barrel to get up and down and front to back movement, then another camera just off bore axis to look at left to right and up and down movement. You'd need a really stable mount for the out-front camera. The 100K frame rate would be a limiting factor for measuring the higher frequency harmonics.
Getting the whole 3-dimensional movement and resonance picture versus time is achievable if you want to invest heavily. But you'll be limited by the equipment and if you are having a shooter on the gun - as opposed to a rail gun kind of setup - the user error part can be expected to add a bunch of error sources that may be very difficult to understand.
The logic Litz uses is certainly part of the picture if your goal is to be accurate and precise - which is what we all want. Think about the ELR rifles you enjoy the most, and those that are more challenging. A rifle that fits you and is set up to keep the bore better aligned (after firing) with the POA instills confidence, in part because your field of view stays much more on target, you can spot more of your hits and misses, etc. I don't doubt that a tuner can lower resonance in a barrel, but I'm not convinced that the optimum solution has been found just yet.
i think this is the core of the issue
we need to define what we are really looking for
its seems (if they work or dont):
that tuners arenot a one size fits all solution
shooter needs to really know his rifle and load
the idea of thinking that anyone can buy 1 of 4 size /style tuners will never happen
but buying the exact tuner designed (i would think from a pile of interchangeable parts) for your specific rifle/barrel/profile is a possibility
if we all agree on that then the tuner threads move in a different direction
if the thought is that 1 tuner rules them all, then we just go in circles
??
A couple of antidotal observations:
Does a loose wobbly tuner or brake affect accuracy, sure has when it's happened to me..
I've had a brand-new Remington factory 6.5, shoot no better than 1.5MOA. Strapped a Magneto speed to it to see what the heck might be going on with the velocity of the ammo, and to my surprise, groups shrunk to <.75 MOA. This was absolutely repeatable with three of us at the bench. Needless to say, but will anyway, that gun had it's factory barrel spun off and shoots .375-.5MOA with a proof barrel.
I've seen big heavy hunks of rubber help lower the group size on a pencil-weight magnum barrel.
I am sure in some situations, tuners can help, if in some situations they can hurt.
All this said:
After a very long-time using tuners, on heavy-weight match guns, I no longer waste my time and energy on them, I just do NOT see the difference inside my CEP on a well-tuned PRS type match gun sporting a heavy barrel.
Keith shoots our sticks. Tuners…..there are good ones and bad ones and not for everyone or fit every application.
Think of the rail guns used in BR shooting and also used for accuracy test gun set ups in ballistic labs also called a return to battery rest. The rail guns clamp on the barrel back just in front of the receiver. Action floats out in the wind. Just by changing the inch pound settings on the clamp bolts will effect the tune of the barrel and how it shoots.
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Side question.
Do rail guns really need to use the barrel block/clamp configuration for best accuracy or is it just easier /better to mate surfaces on a cylinder 360 degrees and such
so it just so happens that barrel clamps are the most accurate but also the most accurate.
Kind of a self filled prophecy etc
Thanks.
