Advice for Bryan Litz on barrel tuners.

[Curious]

There are a lot of ways to setup a tuner/snubber for benchrest shooting


start with finding your seating depth and load without the tuner/snubber on
with tuner screwed all the way on fire one shot then turn the tuner out 180 degrees
fire a second shot at the same bull
continue this firing one shot move 180d fire a second shot until two shots go in the same hole with 180 degrees of tuner movement you are then in the widest window.
it may take several full revolutions until this happens but with a good bench rifle chambered in a BR caliber it will happen

Thats interesting while also giving me more questions than answers.

If you optimise your load without the tuner installed then add the 3-8oz a typical tuner weighs then surely that could throw that good load right into a scatter node?

As such you are then starting your tuning from a bad place and not a good one?

Ive seen nodes come and go within half a turn depending on barrel stiffness and tuner weight/thread pitch so half turn increments would seem to miss out so much and you might never find yourself in the accuracy nodes as they could be half way between the two 180 degree opposed settings?

 

[boltfluter]

Logically, one would think you can stop movement at that joint by a jam nut or similar, but you really can not. At higher frequencies, every joint in the system moves. Same principle as bolts working loose on old cars etc. You torque it tighter than hell plus a round and a half...come back 3 months later and it's loose again. Vibration and temp changes are the cause. Same with a tuner. There is inevitable movement at that joint...it can't be totally stopped. My design is based in part on that very thing. It manages and dampens that inevitable movement rather than pee'ing up a rope, trying to stop it altogether. Short of welding it solid, it can't all be stopped. There is also some logic that actually implies some movement at that joint is not a bad thing, if managed to where it's consistent rather than random. It's freedom of movement that actually allows the particle dampening aspect of my tuner to be effective. It took a while for people to accept that something moving inside of my tuner could be good. I got questioned on that a lot early on. A few world records and national championships later, I don't get that question much any more. Not that you can't build a good tuner but I'd look elsewhere for improvement. I build mine like that for good reason.

Case in point, and I found this extremely interesting.
When doing vibration testing, one of the guns was a glue and screwed setup. During live fire testing, we established some number with it setup that way. The interesting part came when I decided to try something for grins...I pulled the scoped and action screws, laid an iron on the action and waited. When it was ready, I pulled the barreled action from the stock. It came out tight and left a beautiful bedding job behind. I waited for it to cool off and put the gun back together and torqued the screw back in. It was very snug going back into the bedding. Now the good part...the gun was vibrating at a completely different frequency! Moved the tuner a couple of marks and it went right back to shooting just like it did before but still at a different vibrational frequency, which proved, there was movement, even at that perfect bedding joint, torqued tight..60in/lbs iirc. Bottom line here...glued is unitized..stock and barrelled action. Screwed is still two parts and even with perfect bedding, there is high frequency movement. Not saying it hurts anything but it does in fact move. Kinda like using a torch to cut a seized bearing race from a shaft. Done right, you won't nick the shaft because the heat doesn't transfer to the other part..the shaft, in the same way, even though it may well be a press fit. Hope some can relate to that as I do. I'm just an old farm boy.

This also supports a couple more points that I make on here from time to time. One being that tune repeats over and over. We were two marks away from a sweet spot after screwing it all back together but not at the same frequency now, but a totally different vibrational nodal point.

The other point this supports is that tuners alter phase time..IOW, we manipulate where the sine wave is when the bullet exits. That's why such small increments have such a profound affect as well why the group shapes are predictable and repeatable at different settings between completely in to completely out of tune.

Very interesting test you did. Makes one think. Thanks for sharing.
Paul

 

[Gato]

This was the second time I had done the test identically and came out with the same results both test. I don't need Brian Litz or anybody else to tell me whether a tuner works or not.

I have the EC Tuner too and lean towards "it appears to work with my small sample tests." But I encountered the same inconsistencies that Litz did which made me question whether it was just luck or not. For example, I found 8.5 on the tuner to be a tiny group, I explored more settings and then came back to confirm it and the group opened up. Retesting in the same session showed 6.5 was the good setting now. There are other things too but I don't seek to become a high-level shooter. I just don't have the time, so I'm not as stringent as I could be about it.

I also don't rule out that my groups get better not because I'm turning the tuner, but because I've settled into the rifle more and simply shooting better.

 

[Dusty Stevens]

I have the EC Tuner too and lean towards "it appears to work with my small sample tests." But I encountered the same inconsistencies that Litz did which made me question whether it was just luck or not. For example, I found 8.5 on the tuner to be a tiny group, I explored more settings and then came back to confirm it and the group opened up. Retesting in the same session showed 6.5 was the good setting now. There are other things too but I don't seek to become a high-level shooter. I just don't have the time, so I'm not as stringent as I could be about it.

I also don't rule out that my groups get better not because I'm turning the tuner, but because I've settled into the rifle more and simply shooting better.

Maybe a different tuner is in order. I have seen the same issues on some

 

[memilanuk]

That... or fliers work both ways. Sometimes they go *into* the group. Nobody likes to admit it, but reality sucks sometimes

 

[blundby]

We should be glad someone is doing scientific testing and not just listening to their buddys and going by "feel"..

 

[gunsandgunsmithing]

We should be glad someone is doing scientific testing and not just listening to their buddys and going by "feel"..

Real scientific testing was and is being done using vibration analysis and engineering, as well as fea analysis and modeling that all shame what you are referring to as a scientific test by Litz..in this case. As I've said several times already..I have great respect for him and most of his works and that this test seems very far beneath his body of work as a whole.

 

[blundby]

Just as with the effect of annealing, I think that if there is a need for ultra-intricate methodology to detect a significant effect of barrel tuners, there really is little to gain.... It is interesting to me that in an area which is so accessible to experimental testing such as shooting/reloading, there is so much reliance on theory unsupported by empirical evidence. I am as guilty as everyone, using AMP annealer, neck turn etc. I used to load looking for powder/velocity flatspots (Satterle method), but the flat spots are just noise and the procedure is worthless.

 

[dgeesaman]

Real scientific testing was and is being done using vibration analysis and engineering, as well as fea analysis and modeling that all shame what you are referring to as a scientific test by Litz..in this case. As I've said several times already..I have great respect for him and most of his works and that this test seems very far beneath his body of work as a whole.

Brian’s first round of testing was built on the possibility that tuners might be helpful to the broadest possible classification of shooting disciplines in simplest of all usage cases. Scientifically, he followed the principle of keeping it as simple as possible to start. He did come back after his first test using a modified protocol, which was to use individual tuning instructions from each tuner supplier, but that didn’t yield significant improvement. It would have been great to see him keep going, but I honestly think tuners are out of reach of his rigorous methodology.

I think those who use tuners, use them best for benchrest and Brian’s equipment and methods simply don’t transfer over to benchrest shooting. There’s nothing wrong with the scientific method, it’s that the equipment wears as you go and it happens fast enough to spoil statistical significance. Yet we see benchrest techniques outperform everything else consistently so we know they work as a whole.

Analysis isn’t scientific method. It’s a prediction tool. Opposite sides of a useful coin. I’ve seen some pretty interesting stuff come from analysis, but the physics still remains too rich (too many sensitive variables to control) to thoroughly validate the models. Anything that comes from FEA needs to be thoroughly tested in the real world for correlation.

Turns out tuners aren’t plug and play enough to show on Brian’s test. But nobody uses them that way. The excellent tuner I bought from you isn’t used that way and so as I read the test i knew his testing doesn’t apply to my use case either. But it works when used as intended. Perhaps there is someone making tuners who is making fairly outrageous claims that led to all of this.

 

[BoydAllen]

When someone says that their tuner setting did not repeat, the first thing that comes to mind is to wonder if the ambient conditions were identical, and after that, the moisture content of their powder. Tuners do not make these considerations go away.

In the past, with a good rifle and components, I would make note of all the details of a load that had just shot very well, and then come back on another day and under the same ambient conditions test the same load. Invariably a slight adjustment would be needed. I believe that this is because the burn rate of the powder changes as it dries out in my measure, loading at the range. Many have not studied this, but there are some excellent tests out there, and interesting anecdotal data. The other factor that corrupts results is not using wind flags, between the shooter and target. I am always amazed by the number of shooters who do not use them.

 

[CharlieNC]

Dr Geoffrey Kolbe has a nice article, where muzzle vibration MEASURED with and without a tuner demonstrate how the tuner provides positive compensation for accuracy.

 

[Ccrider]

When someone says that their tuner setting did not repeat, the first thing that comes to mind is to wonder if the ambient conditions were identical, and after that, the moisture content of their powder. Tuners do not make these considerations go away.

I believe that this is because the burn rate of the powder changes as it dries out in my measure, loading at the range.

So true. I measured 33.30gr. of n133 on a day with low humidity. It rained for a couple of days. I remeasured the same powder and it weighed 33.38. The change in humidity was enough to throw the load out of tune.

 

[gunsandgunsmithing]

So true. I measured 33.30gr. of n133 on a day with low humidity. It rained for a couple of days. I remeasured the same powder and it weighed 33.38. The change in humidity was enough to throw the load out of tune.

Humidity has a smaller effect than temp but nonetheless, is certainly a factor in tuning.

 

[gunsandgunsmithing]

When someone says that their tuner setting did not repeat, the first thing that comes to mind is to wonder if the ambient conditions were identical, and after that, the moisture content of their powder. Tuners do not make these considerations go away.

In the past, with a good rifle and components, I would make note of all the details of a load that had just shot very well, and then come back on another day and under the same ambient conditions test the same load. Invariably a slight adjustment would be needed. I believe that this is because the burn rate of the powder changes as it dries out in my measure, loading at the range. Many have not studied this, but there are some excellent tests out there, and interesting anecdotal data. The other factor that corrupts results is not using wind flags, between the shooter and target. I am always amazed by the number of shooters who do not use them.

Absolutely! As usual, good points, Boyd.

 

[gunsandgunsmithing]

Just as with the effect of annealing, I think that if there is a need for ultra-intricate methodology to detect a significant effect of barrel tuners, there really is little to gain.... It is interesting to me that in an area which is so accessible to experimental testing such as shooting/reloading, there is so much reliance on theory unsupported by empirical evidence. I am as guilty as everyone, using AMP annealer, neck turn etc. I used to load looking for powder/velocity flatspots (Satterle method), but the flat spots are just noise and the procedure is worthless.

Just because it isn't published in a book does not mean the work and testing regarding tuners hasn't been done. Others came before me, others are currently scientifically testing, and others will come after us. Bottom line is that we are way beyond theory with tuners. We are also way beyond anecdotal results. Just myself, but I've done enough testing, both in a laboratory environment as well as live fire vibration testing that I have been able to quantify values as well as make what some would call theory, happen an an oscilloscope with expected results and repeatedly agree on target. There is a lot more real testing going on than you might be aware of. Real testing, not anecdotal testing alone. But when real testing agrees with anecdotal testing and results, over hundreds of thousands of rounds, there is more to it than guess work. That's the damage that an article like Brian's does. It disqualifies or at least makes people believe that testing is lacking in regard to tuners. The biggest limiting factor is equipment to test at speeds that are needed, but that has come light years in a short period. Trust me though, there is currently and has been significant testing done by people that are over qualified for it, if anything. Vibration analysis is but one specialized area of the engineering field. There are some very qualified people, both currently and previously involved in thoroughly testing tuners. As equipment technology improves, I'm sure there will be more learned.

 

[Bill Norris]

Humidity has a smaller effect than temp but nonetheless, is certainly a factor in tuning.

Temp. changes of 10 degrees most of the time will dictate a tuner setting change.

 

[gunsandgunsmithing]

Temp. changes of 10 degrees most of the time will dictate a tuner setting change.

It very well can. There are factors at play, such as cartridge and powders used but 1 mark on my tuner equates to very nearly .3 of a grain of n133 in a ppc with 68gr bullets. That's also worth about 20° if air density is relatively constant/linear. And, both often result in vertical on target. That's 1 mark on MY tuner.... not necessarily on all makes/models and of course larger cases and different powders will not all have the same characteristics as n133 in a ppc.


edited...20°, not 10°...but again, there are other factors and different tuner designs matter in this regard. Not coincidentally, 2 marks is worth about 40-45°.

 

[Bill Norris]

It very well can. There are factors at play, such as cartridge and powders used but 1 mark on my tuner equates to very nearly .3 of a grain of n133 in a ppc with 68gr bullets. That's also worth about 10° if air density is relatively constant/linear. And, both often result in vertical on target. That's 1 mark on MY tuner.... not necessarily on all makes/models and of course larger cases and different powders will not all have the same characteristics as n133 in a ppc.

Absolutely, this proves that the idea of "set and forget" the tuner is not the best method for realizing best performance from the tuner.

 

[gunsandgunsmithing]

Absolutely, this proves that the idea of "set and forget" the tuner is not the best method for realizing best performance from the tuner.

Right! But there are days that I need to adjust and days that I don't, or less, over the same temp swing. Why that is, is still a bit too theoretical on my part to make any absolute statements about it but I alluded to it in my previous post.
Bottom line here is that smokeless powder turning from a solid to a gas is a chemical reaction and all chemical reactions are temperature dependent. That's why velocity goes up with temp, some powders more than others. The key is that the bbl is still vibrating at essentially the same frequency but the faster bullet is exiting sooner...err out of tune condition.

 

[Ccrider]

An Ezell tuner is totally unsuitable for the vast number of possible tuner applications, its more of a dedicated BR or possibly FClass style tuner.

It requires the barrel to be threaded and is quite a lump in comparison to the number of others out there on the market that will look much better sitting behind a muzzle brake or suppressor. Examples such as the ATS or Cortina tuners, these will find their way onto far more factory type guns or PRS/varminter/hunting style gun purely based on their size and aesthetics.

The discussion is about tuners in general not just the Ezell one and not all about BR use either. As we have already seen Mr Ezell wont talk about tuners in general, only his own and generally by telephone which is his prerogative but not much use to this more generalised open forum discussion.

And before anyone starts suggesting Im trolling Mr Ezell In not, its his tuner and he can decide how he discusses it with his customers, I have stated the facts, nothing more.

Throw a rock under a house and the hit dog will bark.

The whole problem is people talking about things they have not actually experienced. Do you expect Mike to give specific info regarding someone else’s tuner?

Like I said. I was van the trollers if it was my site.

To all of you experienced shooters that freely provide us with the benefits of your experience: THANK YOU.

I am a novice and haven’t proven I can hold my own. But, I do understand the value of one’s time and work. Thank you again. Please don’t let the immature trolls affect your willingness to help out.

Charles