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ShelleyDavidson
01-17-2008, 11:04 AM
I certainly don't want to get in an argument with any of my friends. BUT.... I do think it's important to understand how a tuner works so as to make informed decisions as to how to use them.

The engineers tell me that when you add weights behind the muzzle, you move the vibration node back down the barrel, toward the breech end. When you add weight in front of the muzzle you move the vibration node towards the muzzle and that's desirable.

Try this: take a barrel that's not mounted on a gun. Hold it at the breech end with one hand. Now, start whacking it with the side of a plastic ballpoint pen. It'll make a ringing sound at the muzzle but about 1.5" behind the muzzle the sound will be flat. This flat sound is what a vibration engineer calls a “node.” The node is at a transition area where vibration waves meet and there is very little vibration movement at that spot. Then as you continue to "ring the barrel" further towards the breech end, the barrel will ring again. If you cut the barrel at the node, the node will simply move back down the barrel and will still be about 1.5" behind the newly cut muzzle. But, if you attach a muzzle tuner, and some mass, in front of the muzzle you'll move the node nearer the muzzle. At this time, I believe that having this node near the muzzle will allow for a wider tune window. In other words, the rifle will stay in tune across a wider DA swing than if the node is further back down the barrel.

Having said all of this, both tuner designs will help in tuning the relationship of the time and place when the bullet exits the barrel. This was all demonstrated using Varmint Al's software but it was above most of our heads. (Including mine.)

You can get some real benefit by boring the end of a 1.250 straight taper live varmint barrel (or rail gun). Just bore the muzzle end out to .750 and have the depth at about 1.5". Or by attaching a bloop tube. Both will move the node forwards.

I am not an engineer, I'm just repeating what I learned by carefully listening to the guys who've done this for their living. And, if I've made any mistakes in the above statements, I'd sure appreciate hearing from the engineers.

Shelley

lcw
01-17-2008, 11:23 AM
please help me, I did some research, but found no information, with NBRSA can your tuner be any size as long as you stay within the weight issues for a class, or do you still have to maintain any contour restrictions or is that an IBS issue. Thanks in advance.

Linc

ShelleyDavidson
01-17-2008, 11:30 AM
You are correct. In NBRSA, the tuner is restricted only by overall gun weight. Hopefully, IBS will relax their tuner restrictions at the coming winter meeting.

Shelley

lcw
01-17-2008, 11:37 AM
when I was shooting rim-fire last year it seemed I read where, if you ring a barrel like you described, and measured from the "node" to the muzzle, that distance times 1.5-2 should give an approximate weight needed to move the "node" to the muzzle. Are you finding these tuners to move the node all the way to the muzzle or just forward to some degree???

Thanks for the information. Linc

ShelleyDavidson
01-17-2008, 11:55 AM
At this time, I'm still trying to figure it all out. I know that I'm moving the node forward but to where, I don't exactly know yet. I'm just following the design of Esten Speers who is a retired vibration engineer.

Perhaps Esten will chime in and help me out here.

Shelley

lcw
01-17-2008, 12:44 PM
Thanks for all the information. This whole thing poses a lot of questions that lead to questions that lead to questions, kind of the perverbial domino thing. I do appreciate all you and Gene have done concerning the R & D of this project. Helps us guys who can think but do nothing about it mechanically.


Linc

Bill Myers
01-17-2008, 12:58 PM
Shelly,Just a little info on tuners,I have been using,Makeing tuners for both Center & rim fire for over 10 years & there are a lot of variables that are not even being addressed by some of the centerfire posters that are using them,Jackie stated that most rifles are not in tune,He is correct,Most Rimfire tuners that are being used today are not in perfect tune because most shooters have never been taught the Basic procedure for finding a long tuneing window,I have A tuner on a 6PPC,It weighs 13 ounces & i can move it in or out 3 turns & not affect the POI,The rifle will shoot through 1000 feet of DA change,If i use any less weight ,it will move POI with only slight movement,I have found that you can adjust the tuner & go out of one range & into another range,What you are trying to find is range with a lot of forgiveness.Use can use one of the things that Doctors use to check your Heart,But the Rifle has to be together Bedding affects the tuneing,You need to move the Node out past the tuner,as so to have a window to compensate for changes in the weather.You really need to tune a barrel to itself,The load should not matter.Some of these Hummer barrels that you hear about,They are in perfect tune all by themselves,No 2 barrels are the same,Even the index position of the barrel is very prounced upon the tune of the barrel to itself,Wayne Shaw emailed me about the weight of my Tuner,Its 13 ounces & the Barrel is 25 "long in a HV taper. When listening to the barrels rings to move the node forward,You need too Keep adding weight until you have moved it past the muzzle & the barrels has a dull thud when you tap it,If you do not get it past the muzzle,you will still be close ,but not in the long window the you need. BILL

Gene Beggs
01-17-2008, 01:01 PM
Shelley, you are correct in most everything you say in your post about how tuners work, but without carefully analyzing every word, I cannot state with certainty that every word is true. I have no problem with anything you said; I have been through all of that myself.

Your thinking seems to be more in line with what Bill Calfee says about moving the node fore and aft on the barrel. When Bill first came out with his theory that there is a small, parallel node aft of the muzzle that is completely motionless, I, like so many others, bought it hook, line and sinker; however, after years of experimenting and thinking about it, I have concluded, it is not true. Oh,, it's true in one sense of the word; there is indeed a small dead area that is motionless in so far as vertical and horizontal movement is concerned, but it is far from dead as to where the muzzle is pointing.

I do not wish to argue the point with anyone; we have no way of proving it one way or the other, but we can agree to disagree. Even if it were true and we could indeed move the node all the way to the muzzle by adding enough weight beyond the crown; could we afford to add that much weight to a rifle that is restricted by rules to 10.5 pounds or even 13.5 pounds? Also, adding weight to the muzzle makes the rifle nose heavy.

Rather than trying to "fool the barrel into thinking it is longer than it is" and "moving the node all the way to the muzzle" as Mr Calfee suggests, I choose to work WITH the barrels natural vibration frequency. My tuner simply adds a small, adjustable, 3 oz., weight to the muzzle which enables one to vary the frequency at will.

Your tuner works; absolutely, but it is twice as heavy, far more expensive and consists of three parts rather than two. It also protrudes beyond the muzzle creating at the very least a problem during cleaning. There are many ways to skin cats; they all work, but some are much easier than others.

Shelley, I wish you the best of luck in everything you do. I would never want something as trivial as this to come between us. As far as I'm concerned, all of this is just spitting into the wind anyway. When it comes time for all of us to stand before God and answer for the deeds we have done; what difference will it make? :D

My father was known to drink to excess at times, and he was not always of sterling character, but he was quite a philosopher. One of the things I remember most about him was his saying, "Aw hell son, don't worry 'bout it; one hundred years from now it won't make any difference." :D :D

Later,

Gene Beggs

robdaniel
01-17-2008, 01:06 PM
Gene,
Give me a call if you get a chance or email me.
Thanks,
Rob Daniel
949 307 8218
rdaniel2@sbcglobal.net

Mike Swartz
01-17-2008, 01:12 PM
Question??? Is one to believe that the "track" of the muzzle is strictly vertical?? Or is the "stopping" of the muzzle a multi-axial thing? If the "track" of the muzzle is not circular how does the tuner compensate for the ovality of/ or the ecliptic trace of the Muzzle??

Mike Swartz

ShelleyDavidson
01-17-2008, 01:15 PM
I sure hope you're not expecting an answer, from me, other than "damned if I know." Hopefully someone with more education and knowledge can answer your question.

I am of the opinion that an out of tune gun will shoot both vertical and horizontal. Tuning will help both.

Shelley

jackie schmidt
01-17-2008, 01:32 PM
This entire discussion about tuners really centers around on thing. Making it work within the confines of the Competitive Arena.
Many shooters in The Gulf Coast Region have shot beside me in the past three years and seen me play with the tuner, anylizing the group and attempting to keep the set-up agging at a competitve level.
Many of the questions asked in this thread, and in many others, seem to show that many shooters are ignorant of what can happen at the firing line. It isn't quite as easy as it might seem at first glance.
In short, all I attempt to do with the tuner is get the verticle out of the Rifle. It would be nice if you could sit there and fire numerous three shot groups, anylize the pattern, make small adjustments, and then proceed with the record group. Unfortunatly, it just is not that easy. There have been times when I just simply put the tuner back where it was before, because I couldn't get enough info from a couple of three shot groups to tell me exactly what to do. There are a lot of variables involved every time the trigger is pulled, and these variables are what can cause you to make a bad decision, and make things worse than if you would just have settled for what the Rifle had at the start.
I have thought about modifying my tuner design, but I can't really come up with something better that combines ease of adjustment, plus effective tuning capabilities.........jackie

Kathy
01-17-2008, 01:46 PM
Fiend Shelley:

You're pretty much on the right trac......a properly weighted, muzzle attached barrel tuner, does move the "parallel node" to the exit of the muzzle.

If the weight of the tuner is correct for the physical size of the barrel, the muzzle will actually be completely "stopped"......yes it will.

Shelley, I developed the first muzzle attached barrel tuners back in the early 90's....The physics that made a tuner work back then, have not changed today, almost 17 years later.

As a matter of fact, I have refined the barrel tuner, and how it's used, to the point, that we can now build a tuner of the proper weight for the barrel being used, then it no longer needs to be adjusted.......Yes, this can, and is, being done.

My friend Gene Beggs: "I love ya man"....I mean that.

Your friend, Bill Calfee

JerrySharrett
01-17-2008, 01:52 PM
Shelly,Just a little info on tuners,I have been using,Making tuners for both Center & rim fire for over 10 years & there are a lot of variables that are not even being addressed by some of the centerfire posters that are using them,Jackie stated that most rifles are not in tune,He is correct,Most Rimfire tuners that are being used today are not in perfect tune because most shooters have never been taught the Basic procedure for finding a long tuning window,I have A tuner on a 6PPC,It weighs 13 ounces & i can move it in or out 3 turns & not affect the POI,The rifle will shoot through 1000 feet of DA change,If i use any less weight ,it will move POI with only slight movement,I have found that you can adjust the tuner & go out of one range & into another range,What you are trying to find is range with a lot of forgiveness.Use can use one of the things that Doctors use to check your Heart,But the Rifle has to be together Bedding affects the tuning,You need to move the Node out past the tuner,as so to have a window to compensate for changes in the weather.You really need to tune a barrel to itself,The load should not matter.Some of these Hummer barrels that you hear about,They are in perfect tune all by themselves,No 2 barrels are the same,Even the index position of the barrel is very prounced upon the tune of the barrel to itself,Wayne Shaw emailed me about the weight of my Tuner,Its 13 ounces & the Barrel is 25 "long in a HV taper. When listening to the barrels rings to move the node forward,You need too Keep adding weight until you have moved it past the muzzle & the barrels has a dull thud when you tap it,If you do not get it past the muzzle,you will still be close ,but not in the long window the you need. BILL
Finally someone I can agree with on this tuner discussion. I shot tuners in centerfire all through the 2005 season in all the big shoots. As far as I know no one else did. (If they did, please step forward)

The tuners I shot most was ones Scott Fudd Hamilton made for me and they weighed 11 oz. Many are arguing that a 4-5 ounce tuner will tune any barrel. Agreeing with what TJ Jackson learned several years ago, a barrel has a natural tune condition if you just take the time to find it.

What I found out was that IF a barrel is close to its natural tune configuration, a small amount of weight can probably bring it in. If that barrel, or even that load, is way out then more weight is required more than just 4-5 ounces.

I live where there are a bunch really hot-shot rimfire shooters, some of the best in the nation, the Bristol/Kettlefoot area. Many of them very successfully shoot guns that were built by Bill Myers. I now notice most all of them have epoxied or bolted extra weight beyond the original basic tuner. This tells me again that quite a bit of weight is required, as Bill states above.

In the 2005 season I shot some of the IBS circuit including the IBS Nationals at Fairchance. The tuner restriction for the IBS that year was that the tuner body could not extend outside the profile of the rule defined Varmint taper dimensions. I threaded some barrels to 3/4-40 and made some tuners that were about 6" long and 0.900" diameter. That tuner only weighed 5 oz and that design sucked. For one thing a tuner adjustment with that tuner could move the POI about 3/4" at 100 yards.

I just got an email from an IBS prognosticator and he feels the IBS may adopt tuners at the upcoming meeting by about 3:1. We may be underway for ""The development and encouragement of uniform competition to
achieve the ultimate accuracy in firearms, ammunition, components, equipment and shooting methods."" as it states in the IBS by-laws.

lcw
01-17-2008, 02:40 PM
A question I would want to see answered is if you have any data that compares your aggs with and without a tuner in the "arena of competition" as Jackie phrases it.

The second question would be how did you manage the added weight in the various class restrictions of the ruling bodies??

Thanks in advance. Linc

JerrySharrett
01-17-2008, 02:52 PM
A question I would want to see answered is if you have any data that compares your aggs with and without a tuner in the "arena of competition" as Jackie phrases it.

The second question would be how did you manage the added weight in the various class restrictions of the ruling bodies??

Thanks in advance. Linc
The tuner does work. Will it give me the ability to exceed Tony Boyer's accomplishments? No, for two reasons, first I do not have the ability to do so. So far, no one else has either!! Secondly, I got into benchrest in 1998 when I retired at the age of 58 and purely for the enjoyment of the sport. My ego enhancement program was completed years ago.

My aggs in the 2005 season were better than my norm. For example I finished in the top 35 at the Shamrock, ahead of even some Super Shoot and Nationals winners. If you ever decide to get seriously into the sport you will see that the same dog doesn't always end up with the bone every time.

As to weight restrictions, I have 6-7 barrels that I turned to about 3# 6 oz, straight for about 18", one to loose weight for the tuner and two to make the barrel more responsive to tuning as Bill Calfee and others have suggested.

By the way, where all do you shoot competitive benchrest??

Bill Myers
01-17-2008, 03:01 PM
Jerry,You are on the right track,Scott knows how to make a great Tuner,Along with Lynwood Harrell,As old Bill Calfee says,Once the right weight is there,forget about it,it is tuned to itself,I have seen a lot of centerfire barrels that were out of tune & they needed weight taken off the barrel,not added,Benchmark is in the process of making me a 6 mm barrel,14 twist,3 groove in a reverse taper,This barrel will require less weight &tune easier that the HV orLV barrels.I am going to use on of Harrells Tuners on it,It will be modified to hold up on a centerfire. BILL

JerrySharrett
01-17-2008, 03:12 PM
,This barrel will require less weight &tune easier that the HV or LV barrels.I am going to use on of Harrells Tuners on it,It will be modified to hold up on a centerfire. BILL
Bill, the main problem I had with a stock Harrells/Hoehn was the thread sloppiness. If you take the o-ring out of it there is about 0.008" free-play. If the Harrells/Hoehn is locked down solid it will do fine, with some added weight. A centerfire really rattles the cage of a tuner that is not locked up solid. That is why Scott made my centerfire tuners so that the outside ring was in two parts and lock together like jam-nuts.

Bill Myers
01-17-2008, 03:33 PM
Jerry,Call me ,I can tell you how to make it solid,Its easy..540 778 1782. BILL

lcw
01-17-2008, 03:53 PM
You fellers are a tough crowd when it comes to determing a persons knowledge of how competition works when asking questions.

I am just getting into the competition, last year I finished my first full year of matches in St. Louis. The biggest shoot I have participated in to this date is the East/West in St. Louis last year. I have sent in my entry and hope to be one of the shooters at this years Shamrock, plan to travel to Kansas City for some shoots with friends I have made to this point, will shoot the schedule for St. Louis, and am considering some National participation later in the year. I own a BAT model B and a DS both in Leonard stocks, LCS 45X scopes, enjoy shooting a bunch, and want to learn all I can. Thanks for the information.

How does the smaller contoured barrel take to heat and does it effect one's ability to shoot fast versus the hunt and peck style of shooting???

Linc

JerrySharrett
01-17-2008, 04:04 PM
You fellers are a tough crowd when it comes to determing a persons knowledge of how competition works when asking questions.

I am just getting into the competition, last year I finished my first full year of matches in St. Louis. The biggest shoot I have participated in to this date is the East/West in St. Louis last year. I have sent in my entry and hope to be one of the shooters at this years Shamrock, plan to travel to Kansas City for some shoots with friends I have made to this point, will shoot the schedule for St. Louis, and am considering some National participation later in the year. I own a BAT model B and a DS both in Leonard stocks, LCS 45X scopes, enjoy shooting a bunch, and want to learn all I can. Thanks for the information.

How does the smaller contoured barrel take to heat and does it effect one's ability to shoot fast versus the hunt and peck style of shooting???

Linc

Linc, welcome to the fray. It is a fun ride. Hope to meet you at the Shamrock. Sent my money Monday.

You'll love the Leonard stocks. Terry lives just 15 minutes from me.

As to heat in a thinner barrel, if the barrel is stress free heat is not a problem. That is not to say you can't burn one out though. You will find that barrels are like the rear tires on a rail dragster...expendable.

JerrySharrett
01-17-2008, 04:12 PM
Jerry,Call me ,I can tell you how to make it solid,Its easy..540 778 1782. BILLJust did. Let it ring for 15 minutes. Inez must have you out shoveling snow!!

Lynn
01-17-2008, 04:24 PM
The best approach in my humble opinion is to hire a piano tuner.Take a blank to the piano tuner and let him ring it and mark the barrel.Once the barrel is marked determine the distance to the end of the barrel and its weight.Multipy by 1.5 and if you can make weight your all set.If you can't make weight sell the barrel and get a new one.
A piano tuner will hit the node very quickly and understands everything Bill Calfee is talking about.He might call it the 3rd octave instead of the parrallel node but who cares what its called.
I tuned high frequency electronic waves for 22 years and you can hit the same point 3 different ways.The first way is alot of weight before the node.The second way is alot of weight after the node.The 3rd way is the right amount of weight absolutely in the middle of those two points.
Lynn

burtona
01-17-2008, 04:27 PM
Jerry,Call me ,I can tell you how to make it solid,Its easy..540 778 1782. BILL

Bill, tell us here too here please.

Lynn
01-17-2008, 04:31 PM
Al in your included page I see you have some frequencies listed.One of them is 134.5 Hz.
If we double that frequency to get the second harmonic we get 269 Hz I see in your examples several natural frequencies that are extremely close to a second,third or fourth harmonic.As you know the third harmonic is often very large.I rarely see a natural fequency that close to a harmonic when doing electronic work with waves.
Lynn

pacecil
01-17-2008, 05:28 PM
The vibration mode described here is what occurs AFTER the bullet has left the barrel. It is simply the NATURAL vibration that occurs in all barrels, or bars, when they receive a suddenly applied. and then quickly removed force. In other words you hit or strike the barrel with something. You could do it with a pen or it could be done with a bullet. The shape the bar takes on as it vibrates naturally is described in all physics books and was demonstrated very well by Varmint Al. The vibration pattern will almost always contain a node about 2/3 up the length of the barrel towards the muzzle. The node is a point of minimum lateral motion but it is not zero. The node is the point of maximum angular motion.

Varmint Al's analysis is of vibration that occurs in the whole gun, including the barrel, as a result of the recoil force applied to the face of the bolt. It does not include the force applied by the bullet to the barrel. Whether this bullet force is significant is debatable - some think it is, some don't. Both the recoil effect and the bullet effect are less in rimfire than in centerfire simply because of the forces involved

This vibration that occurs while the bullet is in the barrel is called FORCED vibration. It may or may not take on the same form as natural vibration. It may contain a node or not. It may even contain several nodes. So far I don't think anyone has really proved what vibration pattern exists in the barrel as a result of the forced vibrations from the bullet. It is however the vibration that is taking place BEFORE the bullet exits and thus the only vibration that effects bullet flight. The vibration in a barrel resulting from recoil or bullet effects is mostly in the vertical plane but it will in some guns also occur in planes out of the vertical - this is just impossible to predict. The reason it can't be predicted is because the bullet effect is a result of barrel curvature, and this is very difficult to measure. Probably in most barrels the plane of vibration changes with each vibration cycle.

The effect of a tuner is to change the point in the vibration at which the bullet leaves the muzzle such that you get more consistent lateral velocity or a more consistent angle of departure. The degree of lateral velocity and angle of departure are both determined by just how the barrel is vibrating at the muzzle when the bullet departs. The point at which the bullet leaves the muzzle, which is effected by bullet velocity, is what is most affected by the tuner. A tuner gets it's primary effect by simply adding weight to a barrel. A secondary and lesser effect can be achieved by moving the weight

RvA
01-17-2008, 06:32 PM
pacecil,

Thank you! Finally someone else has figured out there is a difference between dynamic and residual vibrations. Now the real question how can these forces be modeled. I do understand pressure vessels, and a barrel with a bullet running down it even at 22 speeds is a very dynamic pressure vessel. As the bullet will cause besides vertical and horizontal motion of the muzzle it will also induce radial motion too. Iím sure that these motions are not being taking into account right now. But I donít have the knowledge or the software to model this. There must be a way to use FEM to do this, which might also lead to a formula which would get us a real starting point. It would really be nice if could be done, so we wouldnít have to resort to all of this trial and error tuning. Any ideas?

Best,

Roger

Don
01-17-2008, 07:42 PM
pacecil,

Thank you! Finally someone else has figured out there is a difference between dynamic and residual vibrations. Now the real question how can these forces be modeled. I do understand pressure vessels, and a barrel with a bullet running down it even at 22 speeds is a very dynamic pressure vessel. As the bullet will cause besides vertical and horizontal motion of the muzzle it will also induce radial motion too. Iím sure that these motions are not being taking into account right now. But I donít have the knowledge or the software to model this. There must be a way to use FEM to do this, which might also lead to a formula which would get us a real starting point. It would really be nice if could be done, so we wouldnít have to resort to all of this trial and error tuning. Any ideas?

Best,

Roger

Check the index section, Varmint Al has modeled almost all the significant contributing factors;

http://www.varmintal.com/apres.htm

Bill Myers
01-17-2008, 07:48 PM
Jerry & Dave,Jerry,I was out clearing the 2 driveways of snow,i missed your call,THe easy way on the Harrells is to thread the tuner onto the barrel & take the ball plunger out & install a 10/32 set screw ,mine has 2 set screws ,one from each side,it has never moved. BILL

LBaggett
01-18-2008, 10:23 AM
I have been messing with tuners ever since Jackie started beating me with them. My down fall in benchrest has always been tune. I thought if something would help, I was going to try it. Being an unknown area with not a lot of factful proof, I made several different tuner designs. My findings are as follows: These things are dampners and not tuners. Do they work: yes
are they easy to set and use: no!

My findings are the same as Shelley and Bill Meyers. I do exact as Bill has said. When I finally find the perfect setting, I never touch the tuner again. These things are wonderful when you find that perfect spot.

All of my good shooting barrels have the tuners protruding past the muzzle. Also, tuners have to be firmly attached.

I do not make simple adjustments, one to two turns at a time til the verticle is gone.

BigMacky
01-18-2008, 03:30 PM
I'm pretty OK with how to go about finding the sweet spot on any given tuner. But once I find the sweet spot on any given tuner it may not be "THE SWEET SPOT" for that barrel. Maybe the tuner is too heavy or even too light.

How does one go about determining what weight tuner is the right weight tuner? Is there a way other than starting with a "real light" tuner .... going from 0 - 500, adding some weight, going from 0 - 500, adding some more weight .... and so on.

Some people talk about ringing barrels ... other don't believe in ringing barrels but they somehow have a way to figure out the right weight for their tuner ....

Bill Meyer's, I remember in a 6mmbr article it was mentioned that you don't believe in ringing a barrel / rifle .... how do you go about it?

What about Gene Beggs .... you talked about experimenting with different weight tuners ... so you must have a method.

Or Shelley .... how do you go about it?

How to figure out the weight needed for any given barrel / rifle would be a tremendous help that would save lots of people lots of the expensive ammo.

If anyone is willing to share their method it would be great.

I'm sure it would be a big help and appreciated by many.

Fred

Fred J
01-18-2008, 03:57 PM
Fred:
I guess will have to just wait for the next issue. I've been shooting for too many years to count, and I still have trouble understanding the weight issue. When I add extra weight, I have to buy bigger gun cases. After I get the larger/longer cases, I have to buy a bigger truck. It never ends.

Gene Beggs
01-18-2008, 06:33 PM
Question??? Is one to believe that the "track" of the muzzle is strictly vertical?? Or is the "stopping" of the muzzle a multi-axial thing? If the "track" of the muzzle is not circular how does the tuner compensate for the ovality of/ or the ecliptic trace of the Muzzle??

Mike Swartz

Mike, no one else has answered your question and it's a very good one so I'll do my best.

No, the 'track' of the muzzle is not strictly verticle. If there is any curvature in the horizontal plane after the barrel is installed on the receiver, that will cause vibration in the lateral plane when the barrel is fired and it is very unlikely that the stop of the barrel in the lateral plane will coincide with that of the vertical. Such a barrel cannot be tuned, if you get the verticle out, you have horizontal dispersion; if you tune the horizontal out you have verticle. "So what's the answer?" Re-clock the barrel on the receiver so as to hide the curve in the verticle plane with the muzzle drooped to its lowest point.

Gene Beggs

ShelleyDavidson
01-18-2008, 07:24 PM
I'm not an engineer and I don't have any science to find the ideal weight for a tuner. The 6-6.2oz weight of my tuner is simply about the maximum that a light varmint can stand if it's a bit light to begin with. It's easy to add weight to either my tuner or Gene's. Simply part off a piece of bar stock that has the appropriate hole bored in the center. Then you sandwich it between the two threaded weights.

I wish I could be more help but I simply don't know the optimum's on tuners.

Shelley

Mike Swartz
01-18-2008, 10:04 PM
Thank you,Gene.

Mike Swartz

Chisolm
01-18-2008, 10:31 PM
Mike, no one else has answered your question and it's a very good one so I'll do my best.

No, the 'track' of the muzzle is not strictly verticle. If there is any curvature in the horizontal plane after the barrel is installed on the receiver, that will cause vibration in the lateral plane when the barrel is fired and it is very unlikely that the stop of the barrel in the lateral plane will coincide with that of the vertical. Such a barrel cannot be tuned, if you get the verticle out, you have horizontal dispersion; if you tune the horizontal out you have verticle. "So what's the answer?" Re-clock the barrel on the receiver so as to hide the curve in the verticle plane with the muzzle drooped to its lowest point.

Gene Beggs
Gene
Can you tell us your technique for making sure the barrel is indexed so the curvature is in the verticle plane?
James

Gene Beggs
01-18-2008, 11:03 PM
Gene
Can you tell us your technique for making sure the barrel is indexed so the curvature is in the verticle plane?
James

James, I made up a faux receiver of aluminum threaded exactly like the action. Once the barrel is partially chambered and tenon threaded, I place the faux receiver in the chuck and indicate it in, then take a light skim cut off the face so it's running true to the lathe bed. Then screw the barrel in and tighten just snug. Place a dial indicator against the muzzle of the barrel and slowly rotate the spindle. You will quickly locate the position of the barrel that wants to be clocked up at six o'clock. Mark this in some way. I wrap a piece of masking tape around the barrel and mark this spot with a pencil.

Now, take the barrel out of the lathe and screw it into the receiver that it will be installed on and tighten it up. If you are lucky, the mark you made will be on the bottom of the barrel in the six o'clock position relative to the receiver. But if you're like I am, the darn thing will probably be somewhere else. :rolleyes: Let's say the mark is at nine o'clock. This will make it necessary to rotate the barrel 90 degrees clockwise to line it up. If the barrel is threaded 1.063 X 18, you will need to remove .0137 from the tenon shoulder. This should then put the mark at six o'clock. Hope this makes sense. I'm gettin' tired; think I'll call it a night.

Gene Beggs

Chisolm
01-18-2008, 11:34 PM
James, I made up a faux receiver of aluminum threaded exactly like the action. Once the barrel is partially chambered and tenon threaded, I place the faux receiver in the chuck and indicate it in, then take a light skim cut off the face so it's running true to the lathe bed. Then screw the barrel in and tighten just snug. Place a dial indicator against the muzzle of the barrel and slowly rotate the spindle. You will quickly locate the position of the barrel that wants to be clocked up at six o'clock. Mark this in some way. I wrap a piece of masking tape around the barrel and mark this spot with a pencil.

Now, take the barrel out of the lathe and screw it into the receiver that it will be installed on and tighten it up. If you are lucky, the mark you made will be on the bottom of the barrel in the six o'clock position relative to the receiver. But if you're like I am, the darn thing will probably be somewhere else. :rolleyes: Let's say the mark is at nine o'clock. This will make it necessary to rotate the barrel 90 degrees clockwise to line it up. If the barrel is threaded 1.063 X 18, you will need to remove .0137 from the tenon shoulder. This should then put the mark at six o'clock. Hope this makes sense. I'm gettin' tired; think I'll call it a night.

Gene Beggs
Thank you Gene. I sure appreciate all your help.

James

BigMacky
01-19-2008, 06:47 AM
Gene,

When I read about people indexing a barrel most times they shoot a group, rotate the barrel 90 degrees, shoot another group, rotate the barrel 90 degrees, and so on until they find the position that the barrel shoots best in.

Is the indexing that you are talking about and the way you do it using a dial indicator actually doing the same thing without having to shoot groups?

Fred

Gene Beggs
01-19-2008, 06:56 AM
Gene,

When I read about people indexing a barrel most times they shoot a group, rotate the barrel 90 degrees, shoot another group, rotate the barrel 90 degrees, and so on until they find the position that the barrel shoots best in.

Is the indexing that you are talking about and the way you do it using a dial indicator actually doing the same thing without having to shoot groups?

Fred

Exactly.

Gene Beggs

BigMacky
01-19-2008, 07:56 AM
Exactly.

Gene Beggs

I thank you for that valuable information :cool:

Fred

Gene Beggs
01-19-2008, 08:12 AM
Mornin' guys

After a good night's rest and two cups of coffee, I'll try once more to put my thoughts in writing. Yesterday, I spent most of the morning working on a post and as I was nearing completion, my internet service abruptly quit and I lost the entire thing. :mad: Cableone has been installing new equipment and upgrading their service; outages have been very common lately. Hope that doesn't happen today. :rolleyes:

I have read and digested every response to this thread and I'm with every one of you in what you say; however, nothing that has been said invalidates anything I have posted so far. I realize this is a very controversial subject and there are many who have experimented with it, but let me ask you something; do you suppose that maybe, just maybe, I'm telling the truth and know what I'm talking about?

For weeks, I have gone to the tunnel almost every day and practiced what I described in my post on how to use a tuner; it repeats every time. The adjustments are quick, and easy. At will, I can put the rifle completely out of tune and bring it right back using only the tuner. :)

In all of this, two schools of thought have emerged;

1. Those who feel that one should add large amounts of weight beyond the muzzle in order to move the parallel node all the way to or beyond the crown, thereby eliminating the need for adjustments, supposedly, 'stopping' the muzzle. Once set, they leave it alone. Those in this camp regard such a device as a dampener, not a tuner.

2. Those who regard tuners as just that, tuners; a device that enables the shooter to vary the vibration frequency of the barrel at will.


In answer to all of this, I say, "Method #1 is impractical because, even if it were true that there is a parallel node that is motionless and that by adding enough weight to the muzzle you can actually move it to the crown; can we afford that much of a weight penalty in a 10.5 lb., rifle?" And second, adding that much weight to the muzzle makes the rifle nose heavy and disturbs its balance. Third, I do not like the idea of anything protruding beyond the muzzle that interferes with the escape of high pressure gas at bullet exit.

The question is often asked, "How much weight does it take?" For method number one; a bunch, close to a pound in some cases. For method two; not much! I have not found the absolute minimum, but my three ounce tuner works perfectly on both LV and HV barrels.

What is the range of motion of my tuner from one node to the next? One revolution. We divide this into eight parts. The tuner reference mark is placed at 12:00, 01:30, 03:00, 04:30 and so on.

It has been said, "A picture is worth a thousand words." Boyd Allen has been trying to drag me, kickin' and screamin' into the 21st century by walking me through the procedure to download digital images to my computer. Maybe with his help and patience, I will soon be able to post pictures of my stock, tuner, dies, cartridges, etc. Thank you Boyd.

Later,

Gene Beggs

Dick Wright
01-19-2008, 08:42 AM
What you are doing here is a great service to our sport. I hope that others realize this.

I've been playing with tuners for at least three seasons and have found exactly the same thing you have... they work and it is quite easy to find a tune.

It was a good thing for benchrest when you quit driving airplanes and built your tunnel.

Thanks!

Gene Beggs
01-19-2008, 09:52 AM
What you are doing here is a great service to our sport. I hope that others realize this.

I've been playing with tuners for at least three seasons and have found exactly the same thing you have... they work and it is quite easy to find a tune.

It was a good thing for benchrest when you quit driving airplanes and built your tunnel.

Thanks!

Thanks Dick, you made my day! :D

Gene Beggs

Boyd Allen
01-19-2008, 10:54 AM
Gene,

You are quite welcome. It is the least that I can do, considering all the interesting reading that you provide. If I can help anyone else with the basics of digital photography, and posting pictures on the Internet, I will be glad to. My long distance is on a flat rate, so doing a little coaching on the phone costs me nothing, and we are all enriched by the additional information that pictures provide.

Boyd

BigMacky
01-19-2008, 11:04 AM
First of all Gene ..... THANK YOU for your willingless to share this vital information.


In answer to all of this, I say, "Method #1 is impractical because, even if it were true that there is a parallel node that is motionless and that by adding enough weight to the muzzle you can actually move it to the crown; can we afford that much of a weight penalty in a 10.5 lb., rifle?" If weight were NOT a consideration is Method #1 the method that you would use? I shoot Rimfire ARA with no weight limitations plus my rifle is fairly heavy (near 17 lbs) and a 1 lb tuner would not greatly affect the balance ... or at least I don't think it would.


"I do not like the idea of anything protruding beyond the muzzle that interferes with the escape of high pressure gas at bullet exit."
Interesting question ... some believe in "Bloop Tubes" while others do not ... I'm too new to have made up my mind either way for sure.


"How much weight does it take?" Do you have a method for determining how much that weight is?


It has been said, "A picture is worth a thousand words." Boyd Allen has been trying to drag me, kickin' and screamin' into the 21st century by walking me through the procedure to download digital images to my computer. Maybe with his help and patience, I will soon be able to post pictures of my stock, tuner, dies, cartridges, etc. Thank you Boyd."Gene, I have my own Web Space with TONS of room. I can put any pictures that you'd like to use on my space and give you the "LINK" (URL Address) that you would need to copy into your post to get them to show. Just let me know.

Again .... Thanks ... Fred

Butch Lambert
01-19-2008, 11:24 AM
I would like to think Shelley for starting this post. I like it because he stated his reasons for what he does and leaves it like that. I believe we will learn a lot this year. Gene, maybe you are right, we'll see.
Butch

pacecil
01-19-2008, 01:33 PM
When you check alignment of the barrel outside diameter to determine what position to index it to, how do you determine that the bore runs parallel to the o. d. of the barrel? I realize the muzzle can be checked but how do you check the rest of the barrel?

Gene Beggs
01-19-2008, 03:18 PM
When you check alignment of the barrel outside diameter to determine what position to index it to, how do you determine that the bore runs parallel to the o. d. of the barrel? I realize the muzzle can be checked but how do you check the rest of the barrel?

As far as I know, you can't.

After years of studying about it and re-indexing several barrels that would not shoot, I believe this method gives you the best chance of having a winner from the 'git-go.' You really never know what you've got until you shoot it. I remember once at the Buffalo Shoot here in Midland, I had a barrel that you could not get the horizontal out of. You could tune the verticle out with the load, but when you did, it always showed excessive horizontal. That evening, I re-indexed the barrel a quarter turn and the next morning won the small group of the agg with it. ;)

Gene Beggs

Kirk Ethridge
01-19-2008, 09:14 PM
Gene,

i assume when you screw the barrel on your faux receiver, the muzzle rotates

out of center? What part do you want at 6 oclock? (the lowest?)

Kirk