Mitigating Barrel Whip and Harmonics

[kduffy]

Has anyone done any vibration analysis studies? A natural frequency test could allow length to be optimized or dampening provided in the proper location without firing a shot. Many modern cell phones have an accelerometer in them that could be used to find a minimized vibration node to preset the adjustment of a dampener.

There used to be an adjustable barrel support that inlet into the forearm stock and allowed varying pressure as well. I have not seen these advertised in many years. It would eliminate the unsightly rubber donut and perform the same function. Does anyone have any experience with those?

 

[RYEWSKY25284]

Didn't Browning offer some gizmo on one of their rifles to counteract barrel whip a few years back? I don't think it had much of a shelf life.

It was called the "BOSS accuracy system" and not so good.

 

[25WSM]

I have been a custom Smith for 30 yrs and it just ain't hard to make rifles shoot in the 2 and 3s. Any True action of your pick. Buy custom barrel your choice in any contour 3 and above. Straight chamber job with the right throat and a perfect crown. Ftee float the barrel. Decent trigger. Bed the base and rings. Scope of your choice and tune a load. Just the basics done correctly. You don't need any crazy other things just a simple solid build and you will be good to go. Really you do all the hard work developing the perfect load. Building the gun is easiest part. I can take 95% of the Remington 700s and do very little to them to get under 1/2 moa. You can take 95% of tikkas out of the box and work a load to 1/2 moa no problem.
Savages to. 1000 yard benchrest is won on the loading bench. Every body pretty much has a capable rifle. Way capable. So building the rifle I just give all the components every chance they have at being happy together. You owners really make them what they are when you cook and feed them what they like best. Sure some cartridges are easier to load for and some combinations of parts are easier to get greatness from but pretty much anything you want built proper and fed its preference of ammo is going to perform at a very high level. So pick the parts you like the best find a good Smith and just do it. As for recommendations you ask for I build most hunting rigs with #4 or #5 contours for a sporter and still a lot of guys don't mind the weight it's really hard to go wrong with a sendero contour. Lot of guys I build for don't want breaks because of noise and want that sendero for better recoil control on big 30s and 338s. I really don't think one contour really shoots that much better but the sendero is hard to beat. I like the proof research sendero lite they are just heavier than a #4 and shoot very good. All the proof barrels have been very accurate steel or carbon fiber. Look at the top PRS guys proof and bartlein own it. So that would be my recommendation based on 30 yrs of being a master gunsmith. Start a thread of best gunsmith in your area and ask him what actions and stocks he's most comfortable working with and you will be good.
Have fun. Build 2 and have more fun.
Shep

 

[DJ Fergus]

I will try to make this a quick post of harmonics. Bought a beat up 700 30-06 & cheap scope years ago . Done nothing to it at first but shot it, sub 1 moa group after group with Cor loks. I didn't like the front sight on it cause the rear sight was missing. So I took it off. 1.5- 2 moa group after group after I took the sight off. Changed Scopes, same thing 1.5-2 moa. Put the front sight back on, .75- 1 moa group after group again...... Harmonics indeed.

 

[freddiej]

I'm deciding on a barrel contour for a hunting rifle build (300 PRC) and my research on barrels has brought to light the question of barrel whip.

We know that heavier barrels are supposed to be more accurate, but I wonder what can be done to mitigate the loss of accuracy as one goes with a lighter barrel.

I have a theory that fluting a barrel helps mitigate barrel whip. Any thoughts on this?

I also came across a strange contraption on Amazon: "LimbSaver Sharpshooter X-Ring Barrel Dampener." For $9.99, people are swearing that this thing is helping their groups considerably. Is this for real? Is it only helpful to light-weight barrels? Why would this be okay but having a floating barrel be so important?

If no one has mentioned it yet, I have found one great way to mitigate barrel whip and harmonics. A muzzle brake. I have two really buggy whip barreled rifles, they were 1.% or greater guns. after hand lapping they were better but not much, so I went to a guru of muzzle brakes, had both of them fitted with muzzle brakes. instantly went to the range and put the exact same ammo down their pipes and was shooting under 3/4" out of each. those of you whom know me know I never use Center to Center as my measurement. it's always edge to edge. That is if I do not specify C to C after the measurement. the first of these rifles is my 270 Win M-70 featherweight carbine, the other was recently sold to a friend, it was an M-70, 25-06 featherweight.
Those limbsaver vibration rings do work I am told, but none of the people I know that use them have ever given me data like before and after installation. so I can not say if or how good they are.
I know one more way of mitigating barrel whip and harmonics, counter lands and groove rotational fluting. don't ask me how this works but it stiffens the barrel and kills much of the harmonics. I had a barrel fluted this way for a client. I shot it before and after, the gun was almost 2 pounds lighter and it shot 1/3 the size of the previous groups. same ammo, same lot, same temp. it also made the gun look very nice with the CeraKote camo pattern on it after the flutes were milled.
just my 2 cents worth. later tatters.

 

[DJ Fergus]

If no one has mentioned it yet, I have found one great way to mitigate barrel whip and harmonics. A muzzle brake. I have two really buggy whip barreled rifles, they were 1.% or greater guns. after hand lapping they were better but not much, so I went to a guru of muzzle brakes, had both of them fitted with muzzle brakes. instantly went to the range and put the exact same ammo down their pipes and was shooting under 3/4" out of each. those of you whom know me know I never use Center to Center as my measurement. it's always edge to edge. That is if I do not specify C to C after the measurement. the first of these rifles is my 270 Win M-70 featherweight carbine, the other was recently sold to a friend, it was an M-70, 25-06 featherweight.
Those limbsaver vibration rings do work I am told, but none of the people I know that use them have ever given me data like before and after installation. so I can not say if or how good they are.
I know one more way of mitigating barrel whip and harmonics, counter lands and groove rotational fluting. don't ask me how this works but it stiffens the barrel and kills much of the harmonics. I had a barrel fluted this way for a client. I shot it before and after, the gun was almost 2 pounds lighter and it shot 1/3 the size of the previous groups. same ammo, same lot, same temp. it also made the gun look very nice with the CeraKote camo pattern on it after the flutes were milled.
just my 2 cents worth. later tatters.

So your saying spiral fluting in the opposite twist of the rifling?

 

[ROB WHALLEY]

The heavier the barrel the wider the accuracy node.
Fluting is for looks and weight.
The more material the stiffer the barrel
The shorter the barrel the stiffer it is.
If ur handloading none of it matters, tune ur load to the rifle

You say fluting is for looks and weight, they are bi-products of the real reason for fluting... Heat dissipation, thats the real reason for fluting and now you can have spiral fluting creating more surface area thus more heat loss /quicker cooling. But, with fluting comes less material thus more prone to being flexible and whippy.

 

[Mikecr]

Has anyone done any vibration analysis studies? A natural frequency test could allow length to be optimized or dampening provided in the proper location without firing a shot. Many modern cell phones have an accelerometer in them that could be used to find a minimized vibration node to preset the adjustment of a dampener.

It's more difficult than generalized. I tried it once with a laser mic and a fast sampling DAS. This, to capture near muzzle position on bullet exit. But I found from the many vibrations to breadth of physical barrel movements represented a huge scale. Then, filtering to pick out any one vector was a great deal of work and inconsistent from shot to shot.

Ultimately, I failed to gain understanding beyond conceding that this is a very difficult endeavor. The barrel and the gun it's connected to, move all over hell, in every direction, in a bunch of different patterns. The vibrations traveling end to end and roundy roundy are hard to analyze and then harder to correlate with individual results.
I'll be as impressed as anyone when someone succeeds here

 

[Doozy]

I have used the de resonator rings, they work, and they work very well, move the ring 1/2" at a time. I start with the ring just off the forearm tip and move toward the muzzle.

https://www.bing.com/videos/search?...FD7CCDEB706DBA87697BFD7CCDEB706D&&FORM=VDRVRV

A friend invented the Browning Boss system, and they work in spades. Accuracy ends up being a single ragged bullet hole, even with BAR's in 7 Mag, 30/06, and 270 that I have had them on.

Don't over look standard tuners, and they are easy to use, just different...

Harrells precision makes a dandy for $95

http://harrellsprec.com/index.php/products/tuner-brakes

RAS tuner brake

https://www.bing.com/videos/search?...01D3AF49C8E07A5A773301D3AF49C8E07A5&FORM=VIRE

Mike Ezel tuner

http://www.ezellcustomrifles.com/home-3/pdt-tuners/

First time you put a tuner ring on your barrel, you will be impressed. Focus the groups shooting two shot groups...hard to believe just how simple this works.

Outstanding info right here. Thank you so much for taking the time to put this info together.

 

[Radman]

I'm deciding on a barrel contour for a hunting rifle build (300 PRC) and my research on barrels has brought to light the question of barrel whip.

We know that heavier barrels are supposed to be more accurate, but I wonder what can be done to mitigate the loss of accuracy as one goes with a lighter barrel.

I have a theory that fluting a barrel helps mitigate barrel whip. Any thoughts on this?

I also came across a strange contraption on Amazon: "LimbSaver Sharpshooter X-Ring Barrel Dampener." For $9.99, people are swearing that this thing is helping their groups considerably. Is this for real? Is it only helpful to light-weight barrels? Why would this be okay but having a floating barrel be so important?

With my limited knowledge I can attest to, in my opinion, the importance of a free-floating barrel. I am proud of the accuracy of my Savage Rifles and I know that a dollar bill freely slides around the barrels of each.
HERE is why I've replied to you: Of our rifles, just this past summer, I noticed that the accuracy of one of the oldest began to wane, even at close range, when my buddy fired. (This one has the most slender barrel!!!) I watched what both of us were doing with great interest and I quickly discovered that on one particular rest that we were using, instead of resting the far end of this wooden-stocked rifle on the forestock my friend was resting iit on the barrel. I then proceeded to shoot supporting the rifle by the wood and then firing supporting the rifle by the barrel. The difference was unbelievable. While I haven't repeated this test with other rifles with heavier barrels I'll bet that they may offer somewhat similar results. Just 2 cents of barrel feedback.

 

[Edd]

You say fluting is for looks and weight, they are bi-products of the real reason for fluting... Heat dissipation, thats the real reason for fluting and now you can have spiral fluting creating more surface area thus more heat loss /quicker cooling. But, with fluting comes less material thus more prone to being flexible and whippy.

How does spiral fluting create more surface area? What kind of math do I need to know to calculate this?

 

[Rich Coyle]

All fluting increases surface area just like going across a bridge is shorter distance than going down to the bottom and up to the other side.

 

[Mikecr]

There is considerably more surface area exposed(to dissipate heat) with fluted barrels. A curved area(spiral) is longer/greater than a straight area.

 

[Doozy]

In the process of testing the effects of muzzle brakes we found a graphic example of how easy a barrel can flex. This VIDEO was made for a different purpose but It does show the difference the barrel contour makes. When the barrel is big enough the flex/whip is far less and can create different problems if not addressed.



J E CUSTOM

Thank you for this video JE... I actually just bought an APA gen III muzzle brake that allows the user to open ports to tune the downward force. After watching this I realize that opening those ports will likely make barrel whip worse. I'll have to watch for this going forward (as it may be better to keep them all closed). Thanks again.