Crazy Structured Barrels? Anyone seen these?

[MongooseV8]

https://tacomhq.com/structured-barrels/

I get the premise but I dont see any real world performance benefit?

[superdave50]

Says made in USA but is like trying to read an Chinese engineer's description on eBay

[JackEllis]

For those of you familiar with the Varmint Al web site, these guys seem to be channeling him. I've read several of his articles that use software simulations to investigate some of the variables that affect accuracy.

I get their premise, which in a nutshell is to fabricate something stiffer than a varmint barrel. Not my thing, but precision shooters any folks who aspire to vaporize squirrels at half a mile might be interested. Just bring money?

[Fjold]

If you want to know what type, make, material, etc. makes the best barrels all you have to do is look at the equipment list from all the big benchrest matches. No one goes through more barrels than those guys and they would sell their souls for .001" differences in group sizes.

[pratchett]

Their optics gear interests me...

[LynnJr]

I think the late Harold Vaughn said a 4 inch barrel would put the vibration issues to rest.
What these guys have done is to increase the barrels diameter in order to lessen the harmonic issues then drill perpendicular holes to lighten up the weight.
A 3 inch Benchrest barrel in 6mm weighs 57 pounds just for the blank so it can only be shot in unlimited class.
To take advantage of the benefits of diameter without the huge weight issue the Benchrest crowd has gone to tensioned barrels.
Picture a standard 1.200 inch barrel with a 4 inch pipe over the top of it. The muzzle then gets threaded for a jacking screw or tensioning nut.
The recoil lug gets replaced with a shouldered collar similar to a recoil lug.
You then shoot the gun to make the barrel heat up and grow in length and tighten down the tensioning nut at the muzzle with a spanner wrench.
You get the same affect as a $1800 structured barrel but your second barrel is only $350.
I will post pictures soon.

Jack Ellis
If you look at Varmint Also website alot you will read about my record setting tuner gun. He ran the math on it for me and his conclusion was it could shoot even better with a little more tuning.

Edit: The pictures are both unlimited class rifles but you can get a tensioned barrel gun at less than 17 pounds from Greg Tannel and Volquartzen makes them for 22's

[Spyder]

Everything on that page reads like they took an engineering manual, closed their eyes and pointed at words, picked the biggest they could find, and then strung them together with poor grammar.

"Sinusoidal waves that diverge from its natural frequency generate irregularities and non-repeating standing wave patterns that create vibrations."

"Offset radii cored perpendicular to AUX drilling pattern around the chamber to sectionalize harmonics and impede vibrational frequency."

"A deep-hole drill pattern around the bore that uniplanarizes frequencies and resists sinusoidal harmonics via axial compression for advanced recoil mitigation."

[Spyder]

Picture a standard 1.200 inch barrel with a 4 inch pipe over the top of it. The muzzle then gets threaded for a jacking screw or tensioning nut.
The recoil lug gets replaced with a shouldered collar similar to a recoil lug.
You then shoot the gun to make the barrel heat up and grow in length and tighten down the tensioning nut at the muzzle with a spanner wrench.
You get the same affect as a $1800 structured barrel but your second barrel is only $350.

Similar to Dan Wesson revolvers it sounds like?

[divingin]

Similar to Dan Wesson revolvers it sounds like?

I think the assembly is similar, but the goal was different. Lots more force on the rifle barrel (where the aim was to stress the barrel axially to minimize and radial deflection, rather than just hold the shroud on.)

[LynnJr]

Similar to Dan Wesson revolvers it sounds like?

Yes exactly!!!
On a regular barrel the node is close to 2-3 inches back from the muzzle. On a tensioned barrel the node is at the muzzle.
On a regular barrel we want the muzzle pointing upward when the bullet leaves the barrel so slow shots and faster shots will converge at the target.
This happens because the lower velocity shot stays in the bore longer so it leaves when the muzzle is pointed higher.
The faster shot and slower shot will then meet downrange at a given distance. That is how a barrel tuner works.
If the barrel is pointing downward when the slower shot exits the muzzle the two bullets will only widen that gap the further the distance.

On a structured barrel the diameter of the barrel is large and they drill it to stop the unwanted harmonics.

A regular barrel hung from a string sings like a tuning fork when struck and you can actually run your fingers down the barrel and feel the node. On a #17 heavy varmint or 1000 yard taper barrel the node is 2.-3/4 inches back from the muzzle.
If you can design a wind chime you can hang a weight on the end of the barrel to make it resonate and the gun will be easier to tune as well.
A structured barrel a tensioned barrel a stretcher barrel or a tuner barrel are all trying to move the center of the node to the crown of the barrel.
The barrel that Varmint Al modeled for me on his website was actually rung by a piano tuner here in Santa Rosa so we could calculate the correct tuner weight.

All of these methods show a improvement at the target.

Calguns own RickyRacer87 is going to give the tuner a try at 2000+ yards.

[plumbum]

Interesting in that it’s no longer really a rifle and more of a crew operated short range artillery piece. And I thought shooting from strapped in sandbags was cheating

[k1dude]

That's what my barrel looked like after a giant squid grabbed it during my tragic boating accident.

[divingin]

The barrel that Varmint Al modeled for me was actually ring by a piano tuner here in Santa Rosa so we could calculate the correct tuner weight.

So you measured the frequency the barrel resonated at and worked up a tuner weight and placement for it? How close were you when all was said and done?

[LynnJr]

He rang the barrel and marked the 3rd octave location back from the muzzle. You then calculate the amount that piece of barrel weighs and use the Calfee formula for weighting the tuner.

If you know someone who make wind chimes they can set you up or you can go online and look up Tony Purdy(sp) method which is the same thing.

And in a lightgun configuration most of the posters here wouldn't know any difference in a tensioned barrel over a conventional barrel.
The two examples where of unlimited class rifles just to better illustrate what they look like.

[divingin]

Very cool. Thanks, Lynn. My bench gun is 19.5 lbs, I think; most of it is the 1.25" cylindrical barrel.

I'm not doing anything that would warrant putting that much time, money, or effort into play; I am however, interested in what competitive people are doing to enhance accuracy.

Appreciate the info,