Details, Stopped Muzzle, Calfee

K

Kathy

Guest
My friends:

I'm sorry but things are so busy it's hard to get to this machine as often as I'd like...

I've just fit two of the five barrels from SPEC 4, to SPEC 5......Spec 5 has a completely different stock configuation....I'm trying to determine what affect the stock plays in setting a muzzle device for a "stopped muzzle"....

MY friends, I'm attempting to assist you centerfire folks with your muzzle device development.......it's taking a great deal of my time and expense, but the search for accuracy is worth it.....

Some things for you folks to remember as you develop your devices:

The thing I term the "parallel node", you can call it whatever you wish, has some unusual characteristics......if you keep these in mind, you'll find your development will progress faster...

First: The parallel node increases, or, decreases in length as the muzzle oscillations become faster, or slower. Please keep this in mind, it is so extremely important....

Second: Even though the parallel node increases, or, decreases, in length, as muzzle oscillations change, now remember this please; THE EXACT CENTER OF THE PARALLEL NODE NEVER MOVES CLOSER, NOR, FARTHER AWAY, FROM THE CROWN.............

Folks, think very seriously about what I've just written......

Shortly I'll get back on here and continue......I'm sorry, but I'm simply booked with work..........If I wasn't so darn lazy, I could get something accomplished...

Please keep these first two points in mind.....they are the key to "stopping the muzzle".......

More later, your friend, Bill Calfee
 
This is hard on my brain

Bill, I wish you would call the parellel node "THE DEAD SPOT." I think you have referred to this as a dead spot in the past.

In all of the vibration dampening I have seen in the past, rubber was used in conjunction with other properties to aid in isolating the vibrations.

That is one of the reasons I like Jackie's "Tuner". Rubber is utilized in his design.

This is getting too complicated for my old brain cells.

Good Luck............GW
 
Terminology.

This is one of the bold posts that Jackie is talking about in one of the other threads. A node is a point on a waveform. It has no length.

Based on his previous writings, it seems that Bill believes that there is a straight section of barrel present in an oscillating barrel that is otherwise behaving like a wave.

His belief that there is a straight section in this wave is just that - his belief. Hundreds of years of the study of physics and material science do not support this belief.
 
Jetmugg

That, and there is good reason to believe that the bullet out of a typical Benchrest Rifle has already left the barrel, and possibly gone through the target, by the time a lot of this even happens.
It is probably going to dawn on a lot of shooters in the future that there is more to a competitive tune, (ie, sub .200 agging capability) than just controling barrel vibrations........jackie
 
GUYS,

I know it is difficult, if not impossible, BUT if we CAN ignore him, eventually, he WILL go away.

Pray.
 
Free to post at will...

Kathy said:
Friend Wilbur:

I had a couple of free momnets and I thought I add some extremely improtant information to my thread titled "Stopped Muzzle, Calfee"....extremely important information....
Click to expand...


Bill.... The floor is all yours. You are now free to post that extremely important information that you were previously prevented from posting on that closed thread. Let 'er fly, Bill.
 
JettMug

Steve if we move left or right of that one point on a rifle barrel say 1 or 2 degrees from the node how far will the barrel move?
If that doesn't work for you because of the degrees answer this.If we move 1/4 inch on either side of that same one point how far is the barrel moving?

Now if we hang a muzzle weight off of the end of the barrel how much affect will it have on the node and 1/4 inch on either side of it?

I would like to see a comparison between the muzzles total movement and that nearest the node to do a percentage calculation.I know you posted you were a metals expert and could help us.
Lynn
 
Gary Walters

Gary if you take a piece of binder paper out and draw a a single sine wave on it that is 2 inches peak to peak and call it barrel one it will help.

Mark your wave as follows.The start should be 0 degrees.The first peak should be 90 degrees and one inch tall.The point at which it crosses a plane from its starting point to its stopping point will be 180 degrees.The low peak or trough will be 270 degrees and 1 inch low.The stopping point will be 360 degrees.

Now take a second piece of binder paper out and plot your points so they are along a straight line.Now make the 90 degree pint 2 inches tall and the 270 degree point 2 inches low and connect the dots.You should have the exact same frequency but your amplitude has doubled.

If you draw out a third shape usin 1/2 inch peaks and troughs you will see the frequency still hasn't changed only the amplitude.

If you look on either side of a peak or trough you will see what looks like a flattening on the short peaks and a steepening on the high peaks.

As you add weight to a rifles barrel and if you read what Bill Calfee posted above you can see how a broader tuning range is achieved.

It also lets us know when we are looking for the right amount of weight if we are headed in the right direction or the wrong direction.
Lynn
 
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Lynn said:
Steve if we move left or right of that one point on a rifle barrel say 1 or 2 degrees from the node how far will the barrel move?
If that doesn't work for you because of the degrees answer this.If we move 1/4 inch on either side of that same one point how far is the barrel moving?

Now if we hang a muzzle weight off of the end of the barrel how much affect will it have on the node and 1/4 inch on either side of it?

I would like to see a comparison between the muzzles total movement and that nearest the node to do a percentage calculation.I know you posted you were a metals expert and could help us.
Lynn
Click to expand...


Lynn:
There is nowhere near enough information there for anyone to answer your question. Yes, I am a metallurgist, but what you are asking does not appear to be a metallurgy question. I believe that Varmint Al has the best example of modeling the behavior of a barrel dynamically. Perhaps by working with Varmint Al you might be able to simulate some of the different setups you have described above.

SteveM.
 
Kathy said:
The thing I term the "parallel node", you can call it whatever you wish, has some unusual characteristics......

..... THE EXACT CENTER OF THE PARALLEL NODE NEVER MOVES CLOSER, NOR, FARTHER AWAY, FROM THE CROWN.............
Click to expand...

Bill, in your PS Article in PS Titled "Feeling those good vibration again" you made these two statements ...

So when a rifle barrel vibrates, the node, or dead spot, consists of a little section of the barrel that is perfectly parallel. A barrel tuner causes this little parallel barrel section to be moved to the exact crown of the barrel.

See folks, what the tuner does is to displace enough barrel weight in front of the muzzle so the parallel node, or dead spot, is at the exact exit of the crown and it must do this very precisely.

Well you got me on this one .... did you change your mind? Which is OK ... but the problem I'm having is when to believe what you tell me and when not to ....

Could you put a little smiley face next to those statements that I need to believe .... Thanks .... Mike
 
What ever happened to the good old fashion tune. You know, the one where you adjust the powder charge weight, bullet seating depth, primer selection, barrel length etc.?????
 
Butch Lambert

Butch I think Bill is saying that once we have our tuner at the correct spot the exact center of the parallel node will be at the crown of the barrel.We add weight to get it there and once it is there it will never move.

An example would be a 100 hertz wave.If we change the phase of that wave(moved it closer or further from the muzzle)It would still be the exact same wave for our purposes.If we add weight to it the amplitude or amount of up and down would change but it will still be 100 hertz and the nodes will still be at 90 and 270 degrees.

Lynn
 
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Lynn said:
If we add weight to it the amplitude or amount of up and down would change but it will still be 100 hertz and the nodes will still be at 90 and 270 degrees.

Lynn
Click to expand...

Do you have any idea how ridiculous this is. That's like saying north is always north or the edge of a square is always the corner. Sheesh, and to think I'm sitting on a PhD.... We must have went to different schools!
 
Avangorder

I am trying to explain that if the frequency doesn't change the nodes don't change either.I was equating the amplitude with the barrels muzzle as that is what is being dampened.Not everybody viewing is sitting on a PHd.
Don't sit on your PHd explain what is wrong and I will correct it.
If it is correct and it is say so.
Lynn
 
Varmint Al

Al if the barrel is at a node for all 5 shots and the bullets bc and the extreme spread are all equalized why doesn't this work?
Lynn
 
Check the models

Check the FEA analyses at Varmint Al's website. The barrels do not vibrate like a sine wave. They do not move in a natural harmonic pattern before the bullet clears the muzzle.
 
Jettmug

Steve I have looked at all of Al's models and I even sent his website address to the university of purdue so they could take a look at it.I realise a barrels waveshape doesn't represent a perfect sine wave.Very few things do.It looks more like a lot of sine waves all superimposed on themselves.
Lynn
 
What I see in the clouds....

The barrel behavior looks more like a "whipping" motion to me, a result of the breech trying to move backwards while pivoting around the neutral axis, sort of flipping up at the muzzle end as the bullet exits.

Of course, I also saw the profile of a naked lady in the clouds this afternoon, so I may just be imagining the "whipping" motion also.

Steve.
 
Jettmug

Steve when you see any waveshape it is usually many many many waves all acting at one point in time.Three perfect sine waves with a small amount of phase shift look nothing at all like a picture perfect sine wave.I do thank you for your contribution however.
Lynn
 
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