Studies graphing frequencies in barrels?

[tacomHQ]

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.

To your point- vibration/energy will continue or transfer unless it is countered, inhibited or stopped (relative). Our actions are "floated". There is no direct contact from the action to the chassis- including the recoil lug. Action screws are torqued to 30-40inch pounds. More of a safety precaution then a necessity. People call our chassis "dead". The "ting" you hear and vibration in the scope dry firing the gun- is not a good thing. The energy is transferring. The trigger should be dead/thud with no vibration. The vibration of the barrel does not stop at the throat or chamber. It is quite happy to continue an errant journey. Your shoulder and face just become part of the "tune".

 

[Carolinadx]

This would be about at close someone could get to graphing a barrel in order to see pressure spikes in relation to harmonics. Pressure Trace II

Also charting impacts with powder charge increases and looking a point where a higher velocity impacts slightly lower then the previous round with less powder and a slower speed.


View attachment 364308View attachment 364309

I always wondered how fluting affected harmonics.... Next year early retirement should give me the time to play with all these factors.

 

[jimmybrost]

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.

With all due respect, i have no idea who YOU are, and what credentials you have. Sounds to me like you are the one making broad declarations. But I do know who Fred Wells was, and was fortunate enough to spend a great deal of time in his shop. Bill Ruger, Roy Weatherby, and Gen Norman Schwarzkopf, among others, held his opinions in the highest regard. I was simply saying, if you reread my comment, that if your barrel is floated, it should shoot and doesn't, and everything else is right, bedding it solid will often help.

 

[Mikecr]

Roger that
Meant no offence

 

[Teri Anne]

I just watched an interview with John Krieger. Of course barrel harmonics came up. Something he said gave me pause and my brain took off (lol). Does anyone here know of any studies where barrel frequencies were graphed as a bullet was fired?

I wonder if there's knowledge being left on the table? If one could include recorded frequencies into the rifle/load combination equation, could there be such a thing as determining sweet spots for accuracy BASED ON the barrel's harmonics? I know we "get there" with each individual barrel via load development. However, could a frequency map of sorts potentially provide a specific target to develop the load to?

Brain food. Lol

Browning introduced, if I remember correctly what they called their BOSS system which was a tuning system to attenuate these vibrations. I'm sure that there is some data on this somewhere in the archives.

 

[Rhett Crider]

Browning introduced, if I remember correctly what they called their BOSS system which was a tuning system to attenuate these vibrations. I'm sure that there is some data on this somewhere in the archives.

 

[Tulsa Reiner]

I have often wondered if one day there would some day be a "Magneto-speed type" device available that could measure harmonics….I recently received an EC(Eric Cortina) tuner/muzzle break as a Christmas gift from a buddy. Gave it a quick test at the range the other day on one of my PRS rifles, 6.5x47 with a Med Palma barrel. Need to do some more testing, but initial results were intriguing. Shot at 100/200 yards with the break set at 0, 3, and 6. The "0" setting was near identical to the results using my original Area 419 break.
View attachment 364322

This speaks well for EC's tuner.
What size are the smallest squares on each target?

 

[ShootMo]

Browning introduced, if I remember correctly what they called their BOSS system which was a tuning system to attenuate these vibrations. I'm sure that there is some data on this somewhere in the archives.

I'm old enough to remember the B.O.S.S. system. I always wondered why it fell out of favor.

 

[asd9055]

Take a look here

Barrel Harmonics Mode Shape Movies

There are more labs that test and model these, but you'd have to probably pay them for access
Also these guys

RSI - General Reloading Tips

Barrel Harmonics, Timing & Theory

www.shootingsoftware.com

 

[Jeff Heeg osoh]

I'm old enough to remember the B.O.S.S. system. I always wondered why it fell out of favor.

I'm guessing it was the noise, with the ports you almost had to wear hearing protection and that sucks when hunting and trying to hear whats around you. Just a guess as to part of the non-interest.

JH

 

[asd9055]

I'm guessing it was the noise, with the ports you almost had to wear hearing protection and that sucks when hunting and trying to hear whats around you. Just a guess as to part of the non-interest.

JH

I have a few BOSS systems, I thik it fell out of favor because, 1. it was Proprietary, 2. People did not bother to understand it. The noise, could be avoided if you used the BOSS CR, wchich has no ports. I used 10 different calibers with the BOSS, love them all. So easy to tune.
Forward, 30 years laters and a lot of people are buying the E Cortina, or other tunable brakes. Now that the pattent expired.

 

[cornshank]

I just watched an interview with John Krieger. Of course barrel harmonics came up. Something he said gave me pause and my brain took off (lol). Does anyone here know of any studies where barrel frequencies were graphed as a bullet was fired?

I wonder if there's knowledge being left on the table? If one could include recorded frequencies into the rifle/load combination equation, could there be such a thing as determining sweet spots for accuracy BASED ON the barrel's harmonics? I know we "get there" with each individual barrel via load development. However, could a frequency map of sorts potentially provide a specific target to 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.

this could be a barrel vibe tester from the barn.

 

[ShootMo]

Well that's an interesting find! Wonder what it was originally intended for?

 

[Mikecr]

BOSS is IMO still the best tuner system.
I believe it is not just a weight at the muzzle, but included special rubber action bedding as an integral part of the system.
Well, at least the one BOSS gun I've had did.
And I believe it lowered the frequency of summation vibration for easier tuning.

Ok, found it in the patent: "FLEXANE 94" (Devcon) (a two part pourable liquid urethane rubber bedding compound)