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View Full Version : 1 TURN will tune a barrel.... argument??



alinwa
06-21-2019, 01:18 PM
I'm building a tuner with hidden threads. Two complete turns ONLY from stop-to-stop. You start at one end and tune "back" or "forward".... your choice.


Does anyone here disagree that a perfect tune can always be found in less than one revolution?



Does anyone feel you NEED more than one revolution?

sdean
06-21-2019, 03:01 PM
I'm building a tuner with hidden threads. Two complete turns ONLY from stop-to-stop. You start at one end and tune "back" or "forward".... your choice.


Does anyone here disagree that a perfect tune can always be found in less than one revolution?



Does anyone feel you NEED more than one revolution?

I would think it depends on how good of a tune you have before you start to turn the tuner. Weight would make a difference too. I would say itís very possible to accomplish your goal of one rev.

Greyfox
06-21-2019, 03:39 PM
I'm building a tuner with hidden threads. Two complete turns ONLY from stop-to-stop. You start at one end and tune "back" or "forward".... your choice.


Does anyone here disagree that a perfect tune can always be found in less than one revolution?



Does anyone feel you NEED more than one revolution?

I don't have the experience with tuners that many others have, but I do have a little. I currently own five different types and have owned at least one other. My general practice is to go in as far as possible and back out two turns. I have also done the opposite, out as far as possible and back in two turns. Wherever I have started I have found a solid tune within 1/2 turn, with a little research I have found a minimum of 4 locations per revolution, sometime 8. Your plan will work and probably simplify.

YMMV,
Rick

brickeyee
06-21-2019, 06:13 PM
I'm building a tuner with hidden threads. Two complete turns ONLY from stop-to-stop. You start at one end and tune "back" or "forward".... your choice.

Does anyone here disagree that a perfect tune can always be found in less than one revolution?

Does anyone feel you NEED more than one revolution?

It is going to be affected by the stiffness of the barrel itself.

Barrels are for the most part not all that hard.
This makes the vibration less than 'tuning fork' precise.

The mass of the tuner plays with the stiffness of the barrel to allow tuning of vibration.
You are trying to establish a node at the muzzle of the barrel.

This means that the muzzle is not moving nearly as much in actual displacement at the muzzle as the barrel 'rings' when the bullet passes though.

mwezell
06-21-2019, 06:57 PM
It is going to be affected by the stiffness of the barrel itself.

Barrels are for the most part not all that hard.
This makes the vibration less than 'tuning fork' precise.

The mass of the tuner plays with the stiffness of the barrel to allow tuning of vibration.
You are trying to establish a node at the muzzle of the barrel.

This means that the muzzle is not moving nearly as much in actual displacement at the muzzle as the barrel 'rings' when the bullet passes though.

Technically, it's an anti-node but I get what you're saying and agree.

mwezell
06-21-2019, 06:58 PM
I'm building a tuner with hidden threads. Two complete turns ONLY from stop-to-stop. You start at one end and tune "back" or "forward".... your choice.


Does anyone here disagree that a perfect tune can always be found in less than one revolution?



Does anyone feel you NEED more than one revolution?

No argument from me.

brickeyee
06-21-2019, 09:20 PM
Technically, it's an anti-node but I get what you're saying and agree.

No.

It is a node.
An place of lesser movement.

Anti-nodes are locations of maximum movement.
That would make the muzzle be moving even worse.

https://www.answers.com/Q/What_is_a_node_of_vibration

mwezell
06-21-2019, 10:29 PM
No.

It is a node.
An place of lesser movement.

Anti-nodes are locations of maximum movement.
That would make the muzzle be moving even worse.

https://www.answers.com/Q/What_is_a_node_of_vibration

No, anti nodes are the place of maximum displacement, not of maximum movement. Power is out and battery near dead. I'll be back if needed, to expla in further. Maybe someone else can fill you in.

tunermi
06-21-2019, 11:15 PM
I never had a one turn tuner on a PPC or 30 BR until the recent CF Ezell tuner. This tuner
so far has been fairly easy to find the tune within one revolution. However, I have not
used the tuner in a registered match.It may be more difficult to maintain tune
during a day to four days of shooting.
At the SS 2018. I maintained the load and moved the (another) tuner for six days of shooting. I can assure
you that the tuner was moved more than one revolution during a six day time frame.
The bag and rail gun came in 15th place
Most tuners I use are set at a predetermined distance from the end of bore to tuner end for the start of the tune,
I have used tuner weights from 4.2 oz to 16 oz. For the 16 oz tuner( rail gun), I had to call the supplier to get
the start position of the tune(1.6 inches) from bore end to tuner end(16 oz). The lighter tuner(4.2 oz to 10 oz)
are normally started one plus inches from bore end to tuner end. Lots of luck with your one turn tuner.

brickeyee
06-22-2019, 08:01 PM
No, anti nodes are the place of maximum displacement, not of maximum movement. Power is out and battery near dead. I'll be back if needed, to expla in further. Maybe someone else can fill you in.

In this case displacement is movement.

In any case nodes are places of minimal motion.

mwezell
06-22-2019, 08:27 PM
In this case displacement is movement.

In any case nodes are places of minimal motion.
I don't want this to get long so I'll ask that you do your own research on what I'm about to say. You may know this and we are just not understanding each other well.

But, a barrel is not a guitar string...It's only attached at one end, making it a cantilevered beam. You can not physically move a NODE to the end of a barrel...err cantilevered beam. You can put the ANTI-NODE there.

The anti node is in fact the point where the top and bottom of a sine wave occurs. A node is in between the top and bottom anti-node and is where the most movement occurs, fastest....angularly.

Just imagine the barrel moving up and down, with some round-n-round thrown in. With a node being between the top and bottom anti-node, which do we want the bullet to exit the muzzle...the one at either end or the one in the middle? I want mine to exit just prior to the vertical apex of the barrell's oscillation.

I'm aware of tuners and that some extend beyond the muzzle. Some claim that's how a "node" gets moved to the muzzle. If that were how tuners work, a behind the muzzle tuner would NOT work...but they do.

There is no such thing as a "stopped muzzle"...that's just a physical impossibility, but there are areas where the muzzle moves less, at top and bottom.

Again, a NODE can not be moved to the end of a cantilevered beam of a given length.

FWIW, there are several different frequencies and forces action on a gun barrel when fired. A tuner at the muzzle affects the average result of those frequencies and forces....changing the frequency a tiny amount, allowing us to tune barrel to shoot a load optimally, at a given set of conditions, mostly temperature.

jackie schmidt
06-22-2019, 09:25 PM
I'm building a tuner with hidden threads. Two complete turns ONLY from stop-to-stop. You start at one end and tune "back" or "forward".... your choice.


Does anyone here disagree that a perfect tune can always be found in less than one revolution?



Does anyone feel you NEED more than one revolution?

What threads per inch are you using?

chris
06-22-2019, 09:36 PM
he may have one turn to the inch:;);)

alinwa
06-22-2019, 09:39 PM
What threads per inch are you using?

32

alinwa
06-22-2019, 09:42 PM
I'm with Mike.....

From it's inception in the mid-nineties the accepted "spot to tune" has been on the descending ("leading?") or right side of the top of the displacement as mapped on target....

Vibe
06-23-2019, 01:26 AM
Seriously?
This is STILL under discussion?
LOL

Vibe
06-23-2019, 01:48 AM
But, a barrel is not a guitar string...It's only attached at one end, making it a cantilevered beam. You can not physically move a NODE to the end of a barrel...err cantilevered beam. You can put the ANTI-NODE there.

The anti node is in fact the point where the top and bottom of a sine wave occurs. A node is in between the top and bottom anti-node and is where the most movement occurs, fastest....angularly.

Just imagine the barrel moving up and down, with some round-n-round thrown in. With a node being between the top and bottom anti-node, which do we want the bullet to exit the muzzle...the one at either end or the one in the middle? I want mine to exit just prior to the vertical apex of the barrell's oscillation.

I'm aware of tuners and that some extend beyond the muzzle. Some claim that's how a "node" gets moved to the muzzle. If that were how tuners work, a behind the muzzle tuner would NOT work...but they do.

There is no such thing as a "stopped muzzle"...that's just a physical impossibility, but there are areas where the muzzle moves less, at top and bottom.

Again, a NODE can not be moved to the end of a cantilevered beam of a given length
True, a node cannot be moved to the end of a cantilevered beam, but it can be moved to the crown of the barrel. As for the behind the muzzle tuners, they work by changing the amount of displacement that gets propagated to the muzzle by adding mass and inertia to the mid anti-node.

brickeyee
06-24-2019, 04:11 PM
True, a node cannot be moved to the end of a cantilevered beam, but it can be moved to the crown of the barrel. As for the behind the muzzle tuners, they work by changing the amount of displacement that gets propagated to the muzzle by adding mass and inertia to the mid anti-node.

It actually can be.

You need a weight at the very end of the beam.
Like a tuner.

It is often larger than bore diameter on the inside.
The node will than be at some distance BEHIND the additional weight.

By moving the weight you can make the node appear at the end of the barrel bore.

Years ago I had an older F150 pickup with an actual fender mounted antenna.
The tiny ball on the antenna tip moved the vibration node to about 1 inch down on the antenna.

In a light rain you could clearly see the node as the raindrops struck the antenna.