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BAJ
Guest
Can too much weight be added to a tuner making it difficult to tune the ammo? What happens to the harmonics of the barrel with increased weight?
Brian
Brian
Yes you can have too much weight. As to harmonics you are just changing the frequency/wave length by means of the added mass/ length of beam. The weight/length is added to try and bring the null point ( the zero point between the positive and negative halves of the wave length) as close as you can to the muzzle. ( the proverbial "stopped barrel") BY adding too much weight it would be possible to shift into a 2nd harmonic ( for lack of better term) or another way to say it is moving the zero point beyond the muzzel, which puts you back at square one.
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BAJ
Guest
So how do you tell if have added too much weight to the tuner and shifted into a 2nd harmonic?
Brian
Brian
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johngg1
Guest
to much?
if it does not shoot one hole .. it ain:t working...try different speeds at same setting or lots..,,Buck Henry would say welcome to the fools game it never ends.
if it does not shoot one hole .. it ain:t working...try different speeds at same setting or lots..,,Buck Henry would say welcome to the fools game it never ends.
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pacecil
Guest
What is being described as "vibration" probably doesn't apply to the barrel motion that occurs before the bullet leaves the muzzle. The term "harmonics" also doesn't really apply. These are just words that some posters are using that have no real meaning when applied to the bending that is taking place in the barrel under the moments created by gun recoil forces and the weight of barrel and tuner. You can't "shift a barrel into a second harmonic". You also can't move a node to a position where it will be "stopped". Varmint Al showed all this in his work. The node you think is stopped is always moving right along with what might be called a fundamental vibration mode. You could never stop it! Again, all these terms picked up from the natural vibration that occurs after the bullet is gone are meaningless when it comes to what the tuner does. Tuner and barrel weight and length have some predicable influence on what happens to natural vibration but how you might use this to predict effect on accuracy would be just a guess - nothing more!
Back to your original question, Can you have too much weight, answer is yes. In a worst case scenario even the tuner could be too much.Take the tuner off shoot a group as a control for that ammo, reinstall tuner assembly minus extra weights and follow the set up procedure that I listed information to find. Somewhere in that procedure the vertical is going to shrink some. If you do not find this to happen add a weight and repeat. In rare cases you might have to go in the other direction There is no short cut. Strictly trial and error. ( use decent match ammo, yea I know everyone's idea of match ammo is different , but I hope you get the drift)
I apologize if the terminology I used is incorrect, it is the best that I could formulate to try and convey my thoughts.
I apologize if the terminology I used is incorrect, it is the best that I could formulate to try and convey my thoughts.
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bagul
Guest
My layman's understanding of what a tuner does: It alters the frequency of barrel vibration (faster or slower). heavier--- slower, farther from the barrel tip---- slower, and vise versa. we "tune" the barrel such that by the time the bullet is about to exit the barrel, the barrel tip is at its topmost or bottomost position of it's cycle. It is at this 2 position where the barrel tip "freezes" (least angular velocity). -----just my understanding please correct me if i'm wrong.
Yes, you could have too much weight. I tried to tune a rifile I had just received from my smith. I shot it as I recieved it, and was not really happy. So I started to add weights and extra tuners to no avail. Yeaterday, I took all the extra weights and addittional tuners off, and it shot the best it ever had. And to think, all I had to do, was turn the tuner that came with it, three clicks out .
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BAJ
Guest
Thank you, for the information. I am not a benchrest shooter, I am a smallbore position shooter but I try to learn as much as I can from the benchrest guys. So from what ya'll seem to be saying, I can have too much weight, and the reason why I asked is because I believe I may have too much weight on my barrel. I am currently in the process of designing a tuner and I was doing some testing to try an determine how light I could make a tuner that would work effectively. To make a long story short I took my 15" bloop tube off of my rifle, that weighs about 14oz, during my testing and saw my groups shrink tremendously with a particular lot of black box. I need to test some more but I am afraid that my rifle might shoot better without my bloop tube. Only problem is that I can't shoot iron sights without it because my barrel is only 18 3/4" long.
Back to the tuner stuff, however, I am kinda confused now about how they actually work. I realize its controversial but I was under the impression, from previous research, that the tuner was changing the "amplitude" of the wave component of the barrel NOT the frequency. How would changing the frequency of the wave be of any use? From my understanding, changing the amplitude would be the best thing to do because you could theoretically decrease the range of movement. The less range of movement in the wave, the less range of different positions for the bullet to leave the barrel at different places. Is my understanding of this completely wrong?
Back to the tuner stuff, however, I am kinda confused now about how they actually work. I realize its controversial but I was under the impression, from previous research, that the tuner was changing the "amplitude" of the wave component of the barrel NOT the frequency. How would changing the frequency of the wave be of any use? From my understanding, changing the amplitude would be the best thing to do because you could theoretically decrease the range of movement. The less range of movement in the wave, the less range of different positions for the bullet to leave the barrel at different places. Is my understanding of this completely wrong?
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tim in tx
Guest
vibrations do play a part in being out of tune.
the natural vibrations that pacel spoke of can still be present in the from the last shot if you shoot very fast, but the vibrations which effect the accuracy are high frequency,they travel up and down the barrel many times before the bullets exit,because they are traveling vibrations you just dont want the high frequency vibration at the muzzle when the bullet exits.these high freqency vibrations are caused by a few things,firing pin drop,sear drop ,bolt lug lock up and bolt slap,and the case hammering the inside of the chamber and yes even [multi part] tuners can cause these high frequency vibrations .it is kind of like smacking your gun with a hammer right before you pull the trigger .but any tuner will allow you adjust it out and time the exit around those particular vibrations for good scores or groups,you just have to readjust it once in as while with temp change and is nice to be able to tweek it in at any time.but forces other then vibrations are at play here. there is verticle bending or whip of the barrel upon firing caused by recoil forces and the recoil lug being that the barrel is held off centerline by the lug,i beleive this is the primary force deligating the verticle stringing common to "out of tune",now the weight you put on it slows it down and speeds it up,and increases the amplittude as well which is really good or can be equally as bad if you are the wrong side of the slope so to speak.if it were vibrations the bullet would hit randomly not verticly.point being you can tune with any weight from 3 onces to whatever but in which groups come together and then open back up and once more come back together.if you shoot score then you might not see that pattern,but using groups to gauge tune you just add weight untill the rifle groups tight,then fine tune from there.but if you cannot because the adjustments are having little effect you have to add more weight before it respond to fine tuning.you are effectivly changing stiffness by adding weight, but there are a few differing reasons for adding weight but in the general function is to be in tune,the problem is the final settings are only temporary having to adjust for temp swings,but if you know which way to adjust it do it a few times you will get your own formula for adjusting for temps and you are up and running.hope this helps sirs. tim in tx
the natural vibrations that pacel spoke of can still be present in the from the last shot if you shoot very fast, but the vibrations which effect the accuracy are high frequency,they travel up and down the barrel many times before the bullets exit,because they are traveling vibrations you just dont want the high frequency vibration at the muzzle when the bullet exits.these high freqency vibrations are caused by a few things,firing pin drop,sear drop ,bolt lug lock up and bolt slap,and the case hammering the inside of the chamber and yes even [multi part] tuners can cause these high frequency vibrations .it is kind of like smacking your gun with a hammer right before you pull the trigger .but any tuner will allow you adjust it out and time the exit around those particular vibrations for good scores or groups,you just have to readjust it once in as while with temp change and is nice to be able to tweek it in at any time.but forces other then vibrations are at play here. there is verticle bending or whip of the barrel upon firing caused by recoil forces and the recoil lug being that the barrel is held off centerline by the lug,i beleive this is the primary force deligating the verticle stringing common to "out of tune",now the weight you put on it slows it down and speeds it up,and increases the amplittude as well which is really good or can be equally as bad if you are the wrong side of the slope so to speak.if it were vibrations the bullet would hit randomly not verticly.point being you can tune with any weight from 3 onces to whatever but in which groups come together and then open back up and once more come back together.if you shoot score then you might not see that pattern,but using groups to gauge tune you just add weight untill the rifle groups tight,then fine tune from there.but if you cannot because the adjustments are having little effect you have to add more weight before it respond to fine tuning.you are effectivly changing stiffness by adding weight, but there are a few differing reasons for adding weight but in the general function is to be in tune,the problem is the final settings are only temporary having to adjust for temp swings,but if you know which way to adjust it do it a few times you will get your own formula for adjusting for temps and you are up and running.hope this helps sirs. tim in tx