Bouncing off the "parallel Node", Calfee

K

Kathy

Guest
My friends:

First, I'd like to personally thank Mike S for his valuable imput.......

My friends, The most important development in mine, and your lifetime, is my development of muzzle devices, (some folks call them tuners)

We in rimfire have been working with my muzzle devices for over 15 years now, but you centerfire folks are just now getting started.......I'm doing all I can to assist you fine folks with your muzzle device development.....

I do this, at great expense and time to me, because I love accuracy. I was a centerfire benchrester years ago....there is a soft spot in my heart for your sport......

I'm attempting to give information you can use to get the most out of your muzzle devices............

MY friend Lynn said it best: I could give you a fish and it would last you a day, or, I could teach you how to fish, which would last you a lifetime...I am doing the latter..........

BOUNCING OFF THE PARALLEL NODE

The parallel node has length, depending on the speed of the muzzle oscillations.......a stopped muzzle is when one has a proper muzzle device, located properly ahead of the crwon, which forces the exact center of the parallel node to the crown.........

But what happens if one has his muzzle device positioned so he's at the leading, or trailing, edge of the parallel node, not at its exact center?

A hint: As long as the load you're using is absolutely uniform, good accuracy can be obtained......but what if one round gives a slightly higher velocity?

If your crown is at the edge of the parallel node, instead of its exact center, that higher velocity round will shorten up the parallel node, resulting in that shot having to contend with the part-cycle oscillations at the muzzle.....you have a good chance of having a flipper......or, you could get lucky and hit the group.....

This is why we want the muzzle stopped......there's much more....when I have some more time...

Folks, it's simply awesome.....and thanks again to my friend Mike S for your invaluable help..

Your friend, Bill Calfee
 
But then again, if you consider the "Exact center" as a point - just as the normal standing wave model of a node shows - then you avoid that confusion :D


But then there is still the problem of measuring where that point is - to the nearest 0.001" - in order top make sure it IS at the crown.


And the problem of getting that point moved to exactly the crown without some fine adjustment capability in the tuner design.
 
My friends

My friends:

Sorry I couldn't get back sooner but I've been doing final testing on SPEC 5... which by the way has a "stopped Muzzle". I'm afraid I can't address the details of the final test of SPEC 5......that would be un-paid advertising....
even though the results of the test address the subject at hand....but...

A feller, of gal, gets a new rifle, with a muzzle device, rimfire or centerfire, there's absolutely no difference, the muzzle device does exactly the same for both........anyway, they take the gun to the range to test and to "set" the muzzle device......They start "somewhere" with weights or adjustment, if of the screw adjustment type.......they fire a group, or two, find they have vertical in the group(s) then make an adjustment.....at some point they may creep up on a setting, or weight, that kills the vertical......they are tickled..

(what I'm typing here I've done a hundred times in the past myself)

Anyway, they head home happy.....the next week-end they shoot again...they try a different load, or, lot of ammo, different velocity, and man, they got vertical again, on that good setting from last week......

So the impression one gets, I did for years, is, the muzzle device must be adjusted for each ammo speed.......I adjusted for years, a lot of rimfire folks are still adjusting......

But, what most generally happens, is, the shooter with the new gun, and me in the past, just got the muzzle device at the start, or end, of the parallel node.....not the exact center......so yes, as velocity changes, we begin bouncing off the parallel node, and, we have vertical as we now contend, again, with the part cycle at the crown....

Uh oh, my clothes dryer just shut off....I'm just finishing my last load of a weeks worth of laundry.....

I'll type more another time shortly...

Your friend, Bill Calfee
 
My friends

My friends:

I've got a minute so I thought I'd add a little stuff......

A question: How does one know when they have the muzzle stopped?

My friends, some folks say I talk in ridddles.....I don't.....I want folks to think, cause when one thinks through something themsleves, they derive more from it......

So, I would like for you to think about something....remember, the question is; how can we tell when the muzzle is stopped...ok....

When one fires a round through a barrel, something immediately starts happening......anyone know what that is? Water starts forming in the bore, condensate.......

Next question: If water forms in the bore, how does that affect the next shot?

MY friends, let this settle in your mind.........more when I have a few more minutes.......

Your friend, Bill Calfee
 
Friend Lynn

Friend Lynn:

I have always stated this: A muzzle device of the "correct weight for the barrel being used, and, positioned at the correct distance "in front of the muzzle", can stop the muzzle..........every barrel is different......finding the correct weight and positioning is, of course, the challange....sounds like you're getting close.....

MY FRIENDS:

I have a couple minutes and want to add something.....keep in mind, all this is aimed at trying to determine when we have our muzzle stopped....ok..

If I said to you folks; I've got a gun that will "wait for me"......do you know what I mean? Some guns, will wait a minute ot two, while you're waiting out a condition change, and will put the next shot right where you hold...
Most guns won't......most folks know if they're in the middle of a target, or group, and have to wait, they'd better dump that round....keep this in mind...

Got to run for now...

Your friend, Bill Calfee
 
My friends

My friends:

Have a few minutes.....

I want to thank all the folks who went out of their way, some giving all, so I can live in the greatest country on the face of the earth, and be free to do the things I'm allowed to do......I have done nothing to deserve their sacrifice....the folks who served this country, will always have a place in line, ahead of me.....Bill Calfee

NOW MY FRIENDS:

How do we know if we've stopped our muzzles?

Back 30 years ago, when I was heavy into centerfire benchrest, I learned real quick that I could shoot better groups if I could get the shots off fast....My thinking was, back then, that this fast shooting allowed me to get more shots off in the exact same shooting condition.....which is of course true.........

But there's another factor that shooting quickly eliminates; water in the bore.........

MY friends, when condensate developes in the bore, what happens when we shoot the next round.......? Water is a great lubrication..... We get a shot with a different velocity.......and, like I said earlier, if we're just bouncing off the parallel node, instead of having its exact center at the crown, that shot will be affected by the oscillations of the part cycle, and, we can have a flipper....

So what's this knowledge got to do with knowing if we've got our muzzle stopped?

Will get back shortly.....

Your friend, Bill Calfee "GOD BLESS AMERICA"
 
Kathy said:
My friends:
How do we know if we've stopped our muzzles?

Back 30 years ago, when I was heavy into centerfire benchrest, I learned real quick that I could shoot better groups if I could get the shots off fast....My thinking was, back then, that this fast shooting allowed me to get more shots off in the exact same shooting condition.....which is of course true.........

But there's another factor that shooting quickly eliminates; water in the bore.........

MY friends, when condensate developes in the bore, what happens when we shoot the next round.......? Water is a great lubrication..... We get a shot with a different velocity.......and, like I said earlier, if we're just bouncing off the parallel node, instead of having its exact center at the crown, that shot will be affected by the oscillations of the part cycle, and, we can have a flipper....

So what's this knowledge got to do with knowing if we've got our muzzle stopped?

Will get back shortly.....

Your friend, Bill Calfee "GOD BLESS AMERICA"
Click to expand...

I've got a couple of thoughts on that.
I post them later. :D
 
I have to repeat a comment I made a few weeks back.

I was shooting at the range, nice calm conditions. Cold very clean barrel and the first shot goes into the group, rifle is shooting well, several groups in the mid to high 1's.

It is a cool and damp morning, I shoot the rifle a little and then it sits for half an hour on the bench while a talk with the guys there. I come back to it and shoot another group, first shot doesn't go into the group.

I have noticed this before, always after letting the rifle sit with some fouling in a warm barrel !

I wondered if moisture from the atmosphere could get absorbed by the nice warm and dry powder fouling creating a bullet friction condition quite different to a freshly cleaned barrel or a freshly fired barrel.

Bryce
 
Kathy said:
Some guns, will wait a minute ot two, while you're waiting out a condition change, and will put the next shot right where you hold...
Most guns won't......most folks know if they're in the middle of a target, or group, and have to wait, they'd better dump that round....keep this in mind...

Your friend, Bill Calfee
Click to expand...


I would say this is common knowledge to most experienced centerfire competitive shooters, and they will fire a fouler shot if having to wait for more than one minute between shots.

The actual effect probably varies depending upon atmospheric conditions, powder type, and bore variations/conditions..............Don
 
Friend Don

Friend Don:

I quote from you my friend:

"I would say this is common knowledge to most experienced centerfire competitive shooters, and they will fire a fouler shot if having to wait for more than one minute between shots."

Don, yes, it is common knoweldge....but my friend, what if we can use this knowledge to determine if our muzzles are stopped.........I think we can....

Don, I love to deal with folks, like you, who seek knowledge.....not make funnies..

I think this thread is just about to eliminate all the funny folks.......finally..

Then my friend, we can discuss accuracy, in a serious way...

Your point is well taken....

More when I have time.....your friend, Bill Calfee
 
Don

I think it is common knowledge, as you stated, among successful shooters to dump rounds that have sat in a chamber for more than 30 seconds, or to put a round on the sighter if you have let the rifle sit for any length of time between shots.
Granted, I do not know why. It was expalined to me years ago that as what ever is in there cools, it hardens a little more, and probably changes the tune characteristics enough to make a difference.
Of course, sometime we forget to do this. As with all things, our best laid plans can take a backseat to our stupidity at the most opportune moments......jackie
 
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Voo Doo Chemistry

If you let a round "cook" in a hot chamber, heat energy transfers from the chamber wall though the brass case and to the powder inside. This heat transfer warms the powder in the case and lowers the activation energy needed to ignite the powder. (The increased temperature also decreases the deterrent's ability to control the burn rate of the powder.) Since the primer energy remains constant, it can ignite more granules causing the pressure to increase with a corresponding increase in area under the pressure vs. time curve. The increase under the P vs. T curve directly correlates to increased velocity. It has NOTHING to do with "lubricating water" building up in the bore.
 
one pattern i have seen in velocity testing

is when i let the gun sit between shot for 30 seconds or more,70% of the time even without a round in the chamber the next shot will be fast ususally about 15-30 fps ,which does seem to indicate something in the barrel is influincing the flyer.at 1000yds if i have to wait more than 30 seconds and dump the round it will still hit higher on target which influences my holds when this has to be done in the middle of the shooting string.i will still dump the round but it seems is doesnt help a whole lot to do so unless it bakes for a minute or two. tim in tx
 
Mike,

Not trying to argue because I don't know for a fact what is happening but I think there is something in the moisture thing, or maybe a hardening up of the fouling perhaps.

Like I said in my first post, my rifle will put the first shot from a cold but clean barrel into the group. However let the rifle sit for say half an hour after a group with no cleaning and shoot it and the first shot is more likely to go out of the group by up to maybe 0.25.

There is no heat to transfer to the powder and the only difference is the barrel is not clean or freshly fouled but now contains old fouling that has sat a while, cooled and maybe taken on some moisture. It'd be easy for fresh fouling that is bone dry and warm to absorb a bit of moisture from the air, especially on a cool morning down here where the relative humidity is likely to be 90%. I guess it could also be that the fouling has herdened up a bit like Jackie said. Be interesting to chronograph a few shots like this and see if the speed is higher or lower, that'd give a clue to whether the cold fouling is creating more or less friction.

Of course the time frame I am talking about may make whatever is happening in my barrel a different situation to what Bill referred to when actually shooting a group and being forced to wait out a condition.

Bryce
 
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I agree with the concept

Aware that the intent here is to tune a barrel to an extent where delta velocity does not cause delta impact, experience has shown that a hummer barrel cares less how long since the last shot. I'm also certain that I have no idea why but believe if you can up-tune a barrel to hummer status you would see the same.

I can't disagree with Mike since I don't have a enough data but Keith Gantt heated up some rounds uncomfortable to the touch and they shot to the same hole as cold cases. The reason I say not enough data is that Keith's rifle was borderline hummer at the time and pretty much shot anything to the same hole.
 
I would think the heat generated in the barrel would draw moisture if large amounts of humidity or cold weather existed.

In the winter, when ever we weld steel in the shop and it cools during the night, the welded area has a light surface of rust in the heated area.
If left outside, that area would get extremely rusted compared to other parts of the material that didn't get heated.

This is just an observation as I don;'t know whether or not moisture collects inside of barrel after shooting.



Rich
 
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