Studies graphing frequencies in barrels?

[shortgrass]

Barrel harmonics are why BR rifles many times wear a 'tuner'. The "Boss" that was at one time offered by Browning and Winchester is nothing more than a 'tuner',,,,,, used to 'tune' barrel harmonics.

 

[Jeff Heeg osoh]

Barrel harmonics are why BR rifles many times wear a 'tuner'. The "Boss" that was at one time offered by Browning and Winchester is nothing more than a 'tuner',,,,,, used to 'tune' barrel harmonics.

Even some of the Big ELR rifles wear tuners as well nowdays

 

[Radman]

There are so many vibrations going on that I doubt the significant could be predicted.
It would have to be measured to know.

There is the Optimum Barrel Time (OBT) notion about one vibration(from case contact with chamber) traveling back & forth at the speed of sound in steel. The object being to avoid bullet release while a vibration is at the muzzle (opening the bore). It's Chris Long theory.
There are interference waves reflecting from the barrel/action, action/bedding connections, striking and engraving. These are described in Harold Vaughn's 'Accuracy Facts' book.
There is a barrel droop potentially taken out with pressure, causing muzzle whip. And the entire gun vibrating and recoiling. Varmint Al model examples.

I imagine they all add up to system & barrel nodes, which are separate and different from powder nodes (like an OCW).
IMO, working through this to cutting edge accuracy will always take testing.

Extremely interesting. Thanks!

 

[Betarider]

Priobably would be a huge variation of frequencies as there are a huge variation of factors like barrel thickness & length. Some barrels shoot various loads at near points of impact & the harmonics, like sine waves might look sort of like same. Interesting considering $60 plus for 100 bullets, $60 per lb powder with hazmat & shipping & scarce primers.

Now what's the fun in that! No trips to the range, no wore out brass with no load to show from it, no stuck cases in gun or die I just don't see the future that let's you simply pick the bullet you want and it shoots great.

 

[waveslayer]

I think as time and technology progresses you will see more and more accurate barrels that can shoot a range of factory ammo or reloads. It may not be F class grade accuracy but for this form and most guys sub .50 MOA is pretty darn good.

With Doppler radar and guys in ammo companies pushing the envelope, for example the new neckless 277 Fury from Sig, some new barrels and bullets that will be released its fascinating what we will see in the next 20 years. We will all day, back in the day you had to... to get sub moa.

 

[Willys]

Somewhere theres an article about holding your barreled action vertical and pinging barrel like a tuning fork to find the node location at the end and using that info to tune…..?

 

[waveslayer]

Somewhere theres an article about holding your barreled action vertical and pinging barrel like a tuning fork to find the node location at the end and using that info to tune…..?

Well that's a first. I'm curious, and tune your load by? And how?

A bullet leaves a barrel how fast? Measure that at home by?

 

[Willys]

Bill Calfee.

The trick of ringing the barrel is to find the spot were the barrel has a clear ring, held between thumb and finger, then add 1.5 times the weight, of the pice if cut off at that point, the same destance in front of the muzzle as the node is back from the muzzle. Clear as mud? I've made two type's of tuners and they both work neither have a brake and there are 4 shops that are makeing them for sale that I know of. I've never tryed one on a centerfire, but there a must on a rimfire for that BR game.

…"
My centerfire friends:

What I'm going to tell you now, I have never related to another human being.

STOPPING THE MUZZLE

When I run my range tests on the guns I build, the first thing I must do is to determine what tuner weight, and position on the barrel, is necessary,to STOP my muzzle, not just slow it down.

I currently use two lots of Eley EPS ammunition, one has a velocity of 1035 FPS, the other has a velocity of 1075 FPS.

I have a slave tuner that I can quickly attach steel rings of various weights to.

I take 50 rounds of each lot number, switch them at random into two empty boxes. In other words I have the two velocities mixed up so I have no idea which I'm loading in the gun.

I have my base tuner set on its mid-point of admustment with no ring weights.

With the target placed at 42 yards I shoot 5 shot groups and increase, or decrease, the tuner weight, until I get the two different velocities printing in the same group. I'm done. MY MUZZLE IS NOW STOPPED. (This test can be done fairly successfully at 50 yards)

I then start testing various lots of ammo for accuracy.

THE TUNER NO LONGER NEEDS ANY ADJUSTING.... NO MATTER WHAT VELOCITY AMMO I'M TESTING, OR, IN WHAT ATMOSPHERIC CONDITIONS.

Sounds too simple don't it.....it's really that simple.
If you need to fool with your tuner, your tuner is not correct for your barrel.

Your friend, Bill Calfee"

 

[Chas1]

So many variables + lots of time and money...and....then how would one apply it to their unique situation.

 

[ajkellerusmc]

Barrel harmonics are why BR rifles many times wear a 'tuner'. The "Boss" that was at one time offered by Browning and Winchester is nothing more than a 'tuner',,,,,, used to 'tune' barrel harmonics.

I have tried a few of the EZ tuner by Cortina and had some good results.

 

[tacomHQ]

Structured Barrels: reduced harmonics thru a stiffer structure, opposing forces (compression and tension), directed harmonics, greater cooling capacity are all goals in the design of these barrels. Considerable computer simulation has been done on the design. While perhaps not at home on a typical hunting rifle due to size and overall weight the advantages they do bring ... is a worth only determined by the shooter. We are not competing with any carbon fiber wrapped barrel- just like they cannot compete with us 15shots into a 300Norma string. Are a structured barrels nodes reduced: Yes. They will shoot very wide ranges of velocities and bullet weights - wider than any contemporary barrel we are aware of. Will they shoot extended strings with less group drift and ES drift: Yes. Will they allow extended strings and still cool faster after a long string than a standard barrel: Yes.
The first big concern: you can't make a stronger structure than a standard barrel by removing weight. One answer- Airplane wings. Tubes are weight for weight stronger than a solid. If the barrel takes more force to bend .. it vibrates less. In fact our barrels don't care overall if a magneto speed is on the end and essentially don't respond to tuners. Perhaps our lightest versions might respond but at that point we have given up our optimum design.
Weight: PRS guys say make it heavier. F1 the same. In those cases we were required to fit a barrel channel, therefore, a barrel of the same physical dimensions will weigh less than same size solid counter part. A 32" 1.25" barrel will weight about 6.4lbs. We can very precisely project weight as we take not only bores into account but case volumes, throat volumes, threads, brakes...
Reduced felt recoil: If the barrel is not moving as much your not moving as much. Follow up shots are much easier. A well set up gun will allow me to see a 100yd impact with a 300PRC. A 300yd impact with a .375CT.
Heat: not in the same ball park whatsoever. These barrels are radiators not insulators. Our surface area is 3-400% greater than a solid barrel. Flutes don' come close- we can provide that exact calculation. Our chamber is the coolest point on the barrel. A PRS shooter noted their typical group drift occurs at around 20rds. Ours was round 47.
22 guys... a current very well known builder of 22 (very well known) just bought three 22 barrels. He had shot two .416's side by side that were essentially identical except for the barrels.. He was "surprised" to say the least. Totally different recoil. Multiple grain charges shooting within the same group. Extended range performance was excellent with multiple grain weights.
Here is a theoretical: if the barrel is not "moving" as much and the bullet is allowed to run a "straighter" path... what do cars and boats do with direction changes - slow down. I heard a rumor that guys have seen higher velocities- the theory being a straighter path.
Much more is happening as we research new materials, and work at node cancellation other things... not talking about all of that yet.

 

[jimmybrost]

There was a world renowned custom gun rifle maker in Prescott, Az named Fred Wells. Most famous for building African size bolt guns, but he knew benchrest level stuff too. He just didn't like them hahaha. He told me once, if you have a free floating barrel that you can't get to shoot half inch with load development, bed it solid and it'll shoot.

 

[Mikecr]

There was a world renowned custom gun rifle maker in Prescott, Az named Fred Wells. Most famous for building African size bolt guns, but he knew benchrest level stuff too. He just didn't like them hahaha. He told me once, if you have a free floating barrel that you can't get to shoot half inch with load development, bed it solid and it'll shoot.

Whenever someone makes a broad ballistic declaration, -without a list of qualifiers/basis, just do yourself a favor and discount it as BS.
If not by default, then at least consider all the variables left unconsidered with such statements.

I'll suggest one thing that happens when you make a gun solid: it becomes ultra sensitive to resting.
This, because you have removed isolation between the stock & barrel.
Harold Vaughn showed this, and showed that the opposite was far better. That is, to NOT bed even the action, but have ALL free floating.
Granted that was not easy for him to accomplish, to show it. Nor was it viable for anything but the learning. But he pulled it off, and it is valuable information.

 

[RockyMtnMT]

I like both the last two posts. Properly screwed together and doesn't shoot. Bed the whole thing before you toss the barrel. If it doesn't shoot then, toss it.

Free float everything!!! Yep.