Why is it called a "Boattail"?

[1911nut]

OK, I catch a lot of shit around here for showing my ignorance but it is honestly the best way to cure it.

How the hell does a barrel tuner work? I just heard the term when I got on here and started looking them up. They seem very similar to what we used to call a yaw inducing device. We would put them at the end of the barrel to induce a large aerodynamic jump out of the barrel to increase the epicyclic motion of the bullet to make it easier to see with a high speed camera.

I'm guessing these are slightly off center cylinders that you screw into the end of you gun so that you can slightly induce a "jump" to counteract your guns natural "jump"? Is it more complicated that that? Maybe
I should start a new thread talking about the math behind aerodynamic jump?

View attachment 1568081

That‘s not it.

Here’s half of what a tuner does argument

22 Long Rifle Barrel Tuner Analysis -- FEA Dynamic Analysis of Esten's 22LR Rifle with/without a Tuner.

Look up Calfee for the other half….

 

[HappyHellfire]

That is super crude picture. No single post could easily capture what a tuner is and how it works.

Check out the full report on yaw inducing devices at https://apps.dtic.mil/sti/tr/pdf/ADA584062.pdf

 

[gunsandgunsmithing]

Check out the full report on yaw inducing devices at https://apps.dtic.mil/sti/tr/pdf/ADA584062.pdf

Very different.

 

[WSnyder]

Check out the full report on yaw inducing devices at https://apps.dtic.mil/sti/tr/pdf/ADA584062.pdf

After a quick scan (and looking at your previously posted pictures) those are using the gases to alter the flight of the bullet. Tuners do not do that or at least that’s not the designed purpose. Some extend beyond the muzzle and some do not.

 

[Ledd Slinger]

Tuners simply change the harmonic frequency of a barrel as you adjust them in or out. Allows you to adjust to different points of the harmonic wave length where the bullet exits the muzzle into free flight. Could also add that they change the pattern of muzzle gasses, and therefore the effect, it has on the bullet upon exit as well.

 

[WSnyder]

Could also add that they change the pattern of muzzle gasses, and therefore the effect, it has on the bullet upon exit as well.

Unless of course you are using something that doesn’t extend past the end of the barrel such as the very simplistic Beggs tuners.

 

[1911nut]

Could also add that they change the pattern of muzzle gasses, and therefore the effect, it has on the bullet upon exit as well.

Yep, now Happyhellfire should look into bloop tubes used on rimfire rifles and come up with the equations why they work.

 

[WSnyder]

Yep, now Happyhellfire should look into bloop tubes used on rimfire rifles and come up with the equations why they work

Whatever happened with the Purdy method? Is it still being used?

 

[Ledd Slinger]

Unless of course you are using something that doesn’t extend past the end of the barrel such as the very simplistic Beggs tuners.

True. Not all tuners effect muzzle gasses. The comment was more for something like an original version of the EC Tuner where you can adjust it out beyond the barrel crown.

 

[1911nut]

Whatever happened with the Purdy method? Is it still being used?

Yup, guys are still using it to get a starting point.

The Purdy Prescription is a third argument in how tuners work, the harmonics generated in a closed end gas tube.

The Purdy Prescription___(the Rx for tuning your tuner)

The Purdy Prescription Thank You for giving my idea a try. Together we will work thru what I believe will be an effective, if not best, tune for your rifle. My tuning is based on the harmonics that develop in a closed end tube when excited, and putting the muzzle at the even quarter wave in...

www.rimfirecentral.com

 

[gunsandgunsmithing]

True. Not all tuners effect muzzle gasses. The comment was more for something like an original version of the EC Tuner where you can adjust it out beyond the barrel crown.

Most have ample clearance and are short enough and reasonably close in concentricity to not have any negative effect. Too many world records and championships. Simple as that. Now, what he's describing and linked is a different ballgame, even if I can't see why anyone would do that intentionally.

 

[gunsandgunsmithing]

Yup, guys are still using it to get a starting point.

The Purdy Prescription is a third argument in how tuners work, the harmonics generated in a closed end gas tube.

The Purdy Prescription___(the Rx for tuning your tuner)

The Purdy Prescription Thank You for giving my idea a try. Together we will work thru what I believe will be an effective, if not best, tune for your rifle. My tuning is based on the harmonics that develop in a closed end tube when excited, and putting the muzzle at the even quarter wave in...

www.rimfirecentral.com

Since this isn't a tuner thread, I'll just say that I've tested it pretty extensively and while there is some real science to it, it does not seem to apply as I've found no difference in ability to tune with or without regard for it. BUT...if people feel like it gets them close enough to move in very small increments, I'm all for the prx.

 

[HappyHellfire]

That‘s not it.

Here’s half of what a tuner does argument

22 Long Rifle Barrel Tuner Analysis -- FEA Dynamic Analysis of Esten's 22LR Rifle with/without a Tuner.

Look up Calfee for the other half….

So, we always called that barrel whip and it is one of the critical factors in "gun jump" which is different than "aerodynamic jump". Seems that if it was a critical component to accuracy then the gun manufacturers would already be optimizing it.

 

[1911nut]

So, we always called that barrel whip and it is one of the critical factors in "gun jump" which is different than "aerodynamic jump". Seems that if it was a critical component to accuracy then the gun manufacturers would already be optimizing it.

It has been on a limited basis. - look up Browning B.O.S.S

Seems mostly used now by target shooters to wring out the last bit of precision.

Im a bit surprised you know so little about what has been accomplished in the search for accurate rifles. I suggest searching on this site for the topics of your interest.

 

[dellet]

So, we always called that barrel whip and it is one of the critical factors in "gun jump" which is different than "aerodynamic jump". Seems that if it was a critical component to accuracy then the gun manufacturers would already be optimizing it.

It seems like they would also include a decent trigger and stock, which would help almost everybody who buys their rifles. With less effort than learning to optimize a tuner for factory loads.

 

[joshb]

So, we always called that barrel whip and it is one of the critical factors in "gun jump" which is different than "aerodynamic jump". Seems that if it was a critical component to accuracy then the gun manufacturers would already be optimizing it.

Oh Lordy…..you’ve been in the lab too long, my friend!
Most average hunting guys are happy with a lite 2 moa deer rifle and the manufacturers can cheaply make them for the masses. Heavy barreled guns are hard to carry all day, hiking thru the woods. Guys here don’t put up with that and buy custom barrels in heavy contours. Heavy varmint and straight 1.25” barrels are commonly used to reduce “whip”.

 

[JLT]

Patience, gentlemen. This fellow, a Doctor of Philosophy, has done quite a bit of solid research with DOD interest and funding behind said research. The galaxy of alphabet agencies will throw or buy resources directed towards potentially better mousetraps, often resulting in approaches that, at some point in the future, will be recognized as 'before their time'. I came from this academic environment. My doctoral research was funded by the DOD, and they were prepared to throw the kitchen sink at the body of work, provided some glimmer of benefit was objectively in the offering. Sometimes, that bears fruit of far-reaching significance and broad marketability. Sometimes, not so much. The difference between theory and practice can be huge, humbling and, perhaps most importantly, the most significant step toward the next really great idea.

Not all things are known, not all truths have been discovered. An open mind is essential to learning and progress in any field of endeavor. Remember, the 'horseless carriage' was ridiculed before it caught on. One can aspire to be Henry Ford. Or not.