Advice for Bryan Litz on barrel tuners.

[Ccrider]

You guys going to the Tackdriver III?

 

[gunsandgunsmithing]

Nope, don't know who u r, but didn't take long to figure out which game you shoot...who cares, but you? You're the one insinuating which game is superior. I don't care. Shoot what you want, I'll do the same. Don't care, have fun. Come beat me if you have a likin to, you won't be gettin no cherry, and I ain't scared , bring it on...

Later
Dave

Again, two way streets run over here too, even in Ky. You should drop this or say something of substance about your experience with tuners. I've been about as nice as you're gonna get because I had no reason not to be and I think it'd be disrespectful to hammer away on you more, but you're attacking a product that I make and use without anything at all in your posts to back it up. So, that's all. We should both drop it and move on. We just might meet one day and I hope it's a pleasant experience for both of us. Good night D Coots.

 

[gunsandgunsmithing]

You guys going to the Tackdriver III?

No, but I'll make it eventually.

 

[D Coots]

Again, two way streets run over here too, even in Ky. You should drop this or say something of substance about your experience with tuners. I've been about as nice as you're gonna get because I had no reason not to be and I think it'd be disrespectful to hammer away on you more, but you're attacking a product that I make and use without anything at all in your posts to back it up. So, that's all. We should both drop it and move on. We just might meet one day and I hope it's a pleasant experience for both of us. Good night D Coots.

Ya. I never said your tuners don't work, you're in sales, I understand, you get upset when you think someone is bad mouthing your product. Don't think I was??? Have some. When enuf folks beat me with one, I'll use one.

Later
Dave

 

[gunsandgunsmithing]

Ya. I never said your tuners don't work, you're in sales, I understand, you get upset when you think someone is bad mouthing your product. Don't think I was??? Have some. When enuf folks beat me with one, I'll use one.

Later
Dave

No, I'm not in sales. I came from tool and die, hot rods, and farming. I do happen to sell what I make though.

 

[BoydAllen]

Gene didn't use a tuner, he was using a subber as he called it and marketed it back then. Nothing against Gene, but he wasn't in the same universe with Tony in the game. Lot's of guys are still using Gene's snubbers to widen the load window. It must work.

Later
Dave

You are the only one who has described it using that word that I am aware of. Everyone else who used his product calls it a tuner. Who put you in charge of making rules as to how they must be used? Of course you are free to call them whatever you want. I am not arguing with that at all.
BTW, According to Gene, he did adjust his tuners one time for each new barrel.

 

[D Coots]

No, I'm not in sales. I came from tool and die, hot rods, and farming. I do happen to sell what I make though.

Say what? What a coincidence.

 

[D Coots]

You are the only one who has described it using that word that I am aware of. Everyone else who used his product calls it a tuner. Who put you in charge of making rules as to how they must be used? Of course you are free to call them whatever you want. I am not arguing with that at all.
BTW, According to Gene, he did adjust his tuners one time for each new barrel.

Whatever you say Mr. Allen about who put me in charge of making the rules of how they must be used. His Intent was widening the load window. That was why he adjusted his snubbers to every barrel.

I've searched far and wide in many match reports Mr Allen and have not found your name????? What's up?

Talks cheap, takes money to buy whiskey....show me...

Later
Dave

 

[Alfred]

I have been discussing with a friend how to make tuners more stable and perhaps more consistent across time.

It is all about harmonics (Vibration and control of it, I will get to this in a bit).

I think everyone will agree consistency is key, regardless of your discipline.



In effort to lock a tuner down better has anyone developed a tune using shims to be able to torque the tuner against the shoulder of the tenon (If yours uses one) to eliminate uncontrolled/unwanted vibration. By using shims and torqueing the tuner to the barrel, you are essentially making the tuner part of the barrel, or as close as you can get it.

I am looking at pressure turning some shim material soon. depending on the size of your tuner you may be able to use muzzle break shims.

Sure "O" rings and set screws work but I am sure there has to be some vibration in the system. Reading into Brian's data where heaver tuners work somewhat better / more consistent eludes to this theory being correct.

Thoughts?

 

[BoydAllen]

Whatever you say Mr. Allen about who put me in charge of making the rules of how they must be used. His Intent was widening the load window. That was why he adjusted his snubbers to every barrel.

I've searched far and wide in many match reports Mr Allen and have not found your name????? What's up?

Talks cheap, takes money to buy whiskey....show me...

Later
Dave

As far as I remember I have made no claims except having some experience with tuners. It has been a long time since I shot a NBRSA group match, and I have never claimed to be a great shooter, more of a journalist in the field. This the simple truth. I challenged you by asking a question related to what you posted and made a couple of verifiable statements….and rather than argue on subject and answer the question, you changed the subject, which would seem to reinforce my points, rather than convince anyone to the contrary.

 

[Ccrider]

I've searched far and wide in many match reports Mr Allen and have not found your name????? What's up?

Careful Weedhopper. Old Chinese saying: “One does not have to be a proctologist to know an asshole whe he sees one.”

 

[darkangel_r2]

A couple of points. First I agree with I think all of that but, one thing that always stands out to me when I read or discuss tuners from a physics/scientific standpoint is related to amplitude. Physics does in fact teach us that adding a mass to the end of a cantilevered beam should REDUCE amplitude. I won't disagree with that except to bring up an important and usually overlooked aspect of that. We are dealing with a very very short period of time, the time the bullet is actually in the bbl. From vibration analysis testing..the testing shows that amplitude is actually INCREASED during that roughly 1.5 milliseconds while the bullet traverses the bore. And, it makes perfect sense when you consider that the bbl is already deflecting downward before you even pull the trigger due to the weight at the end and gravity. Bottom line...it does in fact increase amplitude for that very short period of time.

It is a driven system so I figured that may happen. The more droop in the bore the more force the barrel puts on the bullet downward and conversely the more force the bullet puts on the barrel upward. My question is in a well setup rifle is the amplitude increase observable in the horizontal plane? I suppose its a dynamic system and a vibration in one plane will migrate around due other real forces putting it off axis.

Next, I consider increased amplitude a good thing..not a bad one because it's muzzle deflection that we see on target, which "talks to us", showing tune or lack of, more clearly on the target. I have tested this a fair amount and have been working with a bbl maker that has made me about 20 barrels in a contour that I spec'd for this purpose..making it slightly less stiff, intentionally. I've found that I prefer this over stiffer barrels to a point and for this reason. It's not drastically different than we already use. It's quite similar to a typical LV contour bbl, fwiw. That also brings up a point about bigger bbls. Fatter doesn't necessarily mean stiffer overall. It is on a per in basis but not necessarily at typical lengths used.

I do not think horizontal vibrations are beneficial. At least I don't know how they are. Vertical can be extremely beneficial if you know how to practically employ them.

An interesting point about barrel stiffness. Some profiles may have less natural droop by reducing mass as they go out. But does that hold true with a load put on the end? Also every barrel has more than just its natural gravity droop as a deviation from center. These small bends and kinks in the bore still act on the bullet and will in turn induce motion in the muzzle. These localized deviations in the bore create a localized bending so the stiffer the immediate section and the more mass forward of this section the lower the amplitude and frequency the corresponding motion at the muzzle should be. Heavy straighter barrels with larger muzzle diameters should help tune out some chaos. Incredibly strait bores may not see significant benefit from this design philosophy.

Last thing that comes to mind is horizontal...Tuners do affect horizontal as well as vertical. A big part of why is twist of the rifling but nonetheless, they do vibrate in all planes, apparently, but are biased toward the vertical plane due to gravity....

I think that's all I was gonna hit on. Ultimately, shooters want to know how to make tuners work for them more than how they actually do it but it is very worthwhile to me and some to have a better grasp on what's going on.

In it simplest terms, tuning is timing bullet exit to ideal muzzle position. This is true be it with a tuner or by changing powder charge.

I ultimately think that's the biggest benefit of a barrel tuner in competition. Instead of pulling out the loading bench and having to change a loads numbers you can just turn a dial on the end of the barrel and drag a good load back to peak performance as conditions change. For people that can't load at the range a tuner is a real game changer.

 

[gunsandgunsmithing]

I have been discussing with a friend how to make tuners more stable and perhaps more consistent across time.

It is all about harmonics (Vibration and control of it, I will get to this in a bit).

I think everyone will agree consistency is key, regardless of your discipline.



In effort to lock a tuner down better has anyone developed a tune using shims to be able to torque the tuner against the shoulder of the tenon (If yours uses one) to eliminate uncontrolled/unwanted vibration. By using shims and torqueing the tuner to the barrel, you are essentially making the tuner part of the barrel, or as close as you can get it.

I am looking at pressure turning some shim material soon. depending on the size of your tuner you may be able to use muzzle break shims.

Sure "O" rings and set screws work but I am sure there has to be some vibration in the system. Reading into Brian's data where heaver tuners work somewhat better / more consistent eludes to this theory being correct.

Thoughts?

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.

 

[gunsandgunsmithing]

It is a driven system so I figured that may happen. The more droop in the bore the more force the barrel puts on the bullet downward and conversely the more force the bullet puts on the barrel upward. My question is in a well setup rifle is the amplitude increase observable in the horizontal plane? I suppose its a dynamic system and a vibration in one plane will migrate around due other real forces putting it off axis.

I do not think horizontal vibrations are beneficial. At least I don't know how they are. Vertical can be extremely beneficial if you know how to practically employ them.

An interesting point about barrel stiffness. Some profiles may have less natural droop by reducing mass as they go out. But does that hold true with a load put on the end? Also every barrel has more than just its natural gravity droop as a deviation from center. These small bends and kinks in the bore still act on the bullet and will in turn induce motion in the muzzle. These localized deviations in the bore create a localized bending so the stiffer the immediate section and the more mass forward of this section the lower the amplitude and frequency the corresponding motion at the muzzle should be. Heavy straighter barrels with larger muzzle diameters should help tune out some chaos. Incredibly strait bores may not see significant benefit from this design philosophy.


I ultimately think that's the biggest benefit of a barrel tuner in competition. Instead of pulling out the loading bench and having to change a loads numbers you can just turn a dial on the end of the barrel and drag a good load back to peak performance as conditions change. For people that can't load at the range a tuner is a real game changer.

You bring up some good points and ask some questions that I don't know the answers to. I might be able to find answers in my notes from vibration testing regarding horizontal amplitude but we weren't really looking at that specifically and it seems illogical that the horizontal amplitude would increase or decrease by adding a weight to the end that will make it more vertically biased, due to gravity. I'll look through some notes and see if anything stands out in that regard.

A couple more points..You mention localized bending. You are likely correct but I look at the bigger picture as I believe there to be multiple frequencies going on at the same time, be it perfectly straight or not, and the the tuner effectively adjusts for the average of all of these, that it "sees" before bullet exit. That's the simplest and best I can explain it.

In terms of bbl stiffness..Lets just take say a 1.250 straight vs a hv contour. Per inch, the 1.25 is stiffer, but it effectively already has a weight at the end, being full diameter all the way out. Make sense? Google lilja barrel weight calculator. His weight program also incorporates a stiffness calculator as well. You can play with the numbers there and it will surprise some people that a bigger bbl is not always stiffer. Length is of more importance. Play with that program. It's pretty interesting if nothing else.

 

[CharlieNC]

My question is in a well setup rifle is the amplitude increase observable in the horizontal plane? I suppose its a dynamic system and a vibration in one plane will migrate around due other real forces putting it off axis.

Analyzing targets which were shot across a charge weight ladder to identify the node based on vertical poi, it is not unusual to find a high correlation for the horizontal as well.

 

[gunsandgunsmithing]

Analyzing targets which were shot across a charge weight ladder to identify the node based on vertical poi, it is not unusual to find a high correlation for the horizontal as well.

I might agree. Can you explain what you're referring to?

 

[CharlieNC]

I might agree. Can you explain what you're referring to?

When I shoot a ladder, for each charge weight I measure the resulting poi deviation for both vertical and horizontal. As normally done I plot the vertical poi vs charge weight to id the node. In addition plotting the horizontal deviation vs the vertical deviation in poi often shows a high correlation, demonstrating the barrel vibration in both planes.

 

[CharlieNC]

When I shoot a ladder, for each charge weight I measure the resulting poi deviation for both vertical and horizontal. As normally done I plot the vertical poi vs charge weight to id the node. In addition plotting the horizontal deviation vs the vertical deviation in poi often shows a high correlation, demonstrating the barrel vibration in both planes.

And when the horz and vert correlate together, that suggest the vibration is actually along a diagonal.

 

[jackieschmidt]

Gene didn't use a tuner, he was using a subber as he called it and marketed it back then. Nothing against Gene, but he wasn't in the same universe with Tony in the game. Lot's of guys are still using Gene's snubbers to widen the load window. It must work.

Later
Dave

I shot a lot with Gene at our local club in Tomball, and watched him break in many barrels, and tune them.

Dave, I tend to agree with you. Gene more or less had a “pet“ load that would use in his new barrels, which would be either a Krieger or a Bartlien. He would adjust the “snubber”, (one piece tuner with a rubber dampening feature), to where he felt the barrel was in it’s optimum vibration node, then start tuning the load in our more conventional methods with load, seating depth and neck tension untill he found his competitive tune.

He would be the first one to tell you he then avoided moving the tuner after that. He usually would tweak the powder charge a little to keep things going.

I sort of follow the same pattern with both my 6PPC’s and my 30BR. I have a load in either that I know will shoot in a cut rifled Krieger or Bartlien, My tuners are also a ‘snubber’ style.

I believe that you can find the correct vibration node that a barrel likes with a tuner, but to finally get the rifle at that magical “.200 or less agging capability”, the load, ie the correct combination of powder charge, neck tension, and seating depth has to be right.

 

[Bill Norris]

I shot a lot with Gene at our local club in Tomball, and watched him break in many barrels, and tune them.

Dave, I tend to agree with you. Gene more or less had a “pet“ load that would use in his new barrels, which would be either a Krieger or a Bartlien. He would adjust the “snubber”, (one piece tuner with a rubber dampening feature), to where he felt the barrel was in it’s optimum vibration node, then start tuning the load in our more conventional methods with load, seating depth and neck tension untill he found his competitive tune.

He would be the first one to tell you he then avoided moving the tuner after that. He usually would tweak the powder charge a little to keep things going.

I sort of follow the same pattern with both my 6PPC’s and my 30BR. I have a load in either that I know will shoot in a cut rifled Krieger or Bartlien, My tuners are also a ‘snubber’ style.

I believe that you can find the correct vibration node that a barrel likes with a tuner, but to finally get the rifle at that magical “.200 or less agging capability”, the load, ie the correct combination of powder charge, neck tension, and seating depth has to be right.

Absolutely Jackie, I found if the powder charge, neck tension, and seating depth is not optimized the tuner will not be at it's full potiential with any load.