Cheap barrel tuner - LimbSaver Sharpshooter X-Ring Barrel Dampener

[GSPV]

Jackie schmidt started that. He had some kind of bushings like that for marine driveshaft vibrations if i remember right

That's the way that I remember it, too.

 

[gunsandgunsmithing]

I've done as much or more tuner testing than anyone, and I'm gonna share something here of value.

I've posted this several times over the years and really left no lines to be read between but haven't been very specific about this, at least often. To be clear, I've never hidden anything about my tuner testing except specific frequency and amplitude numbers. I feel I bought and paid for that data many times over and it's up to others to do the same, if they want to truly learn as much as is possible about what is happening when the gun fires they can. Ideally, they'll do this before posting ideology and theory, rather than after.

This is not earth shattering info to many, any more but, what I've found is that dumb luck works!

The reason is that it takes so very little tuner movement to drastically affect tune, that you can literally luck into a sweet spot about 25% of the time. That's statistically significant, IMHO.

The amount of tuner movement necessary to go from perfectly in tune to completely out of tune with my tuner is about .004" of an inch on a typical hv or lv contour barrel and that tune repeats, over and over again. There are 32 marks around my tuner. There are 32TPI and there are approximately 4 sweet spots in every revolution on a centerfire rifle. CF vs RF matters but not as much as some think. It appears that only amplitude is affected but the natural frequency of vibration changes little, between any caliber, be it rf or cf.
That said, the barrel contours and ammo speeds are considerably different, which does affect how we should tune them.

Bottom line is this...You can move in large swings, as the op has demonstrated but there are two very important factors to consider with doing so.
First...what do you do if it barely goes out of tune and how do you consistently move a rubber a thou or so along the barrel to correct it, methodically.

There is more but that's the gist of my point. Yes, you can stumble upon a sweet spot...but what then?
Tune is mostly dependent upon the chemical reaction change that happens with burning rifle powder as temps change. If you can't be very, very methodical about keeping up with those inevitable changes, there is no point in a tuner at all. Just buy a lottery ticket that offers about a 1 in 4 chance. You'll be better off.

 

[BoydAllen]

Obviously this is not a tuner, but that does not mean that it cannot be useful or improve accuracy. Years ago, I used one in conjunction with a tuner, after testing determined that I got better accuracy that way. A friend who has shot a number of perfect scores in rimfire, has used one mid barrel, on his best rifle, along with the usual accumulation of tuner, bloop tube and weights hung from the muzzle. Just because it is not a tuner does not mean that it is not useful. For every high end custom actioned competition rifle that exists there are probably a hundred that fellows shoot groups with just for personal satisfaction. This may be useful for both groups, but it certainly is not usable for situations where adjustments measured in thousandths are what is called for....not at all.
Added thought: Back in the days when tuners for CF bench guns were more controversial, I used to see a lot of strong opinions posted by folks who had no experience with one. I think that I am seeing the same thing here. No big deal, on forums it happens all the time.

 

[#40Fan]

I hope my original post wasn't thought of as a strong opinion. Only an observation of results achieved. I was happy to see positive results.

I probably did get lucky, too. But, if I hadn't seen that 2 1/2" from the muzzle measurement, I would have been moving the dampener around the best group measurement.

 

[memilanuk]

I did a similar experiment earlier this year with a LimbSaver. It was maybe not as dramatic of a change as what yours showed... but it was repeatable. Problem was, it kinda interfered with the mirage shield. So, I decided to try something related that I'd seen others use: stacks of O-rings. Same spot on the barrel, started adding them two at a time til the groups started opening back up, then started removing one at a time til I had the sweet spot bracketed. Seems to be working okay so far - sample size of 1 and all that.

 

[Ned Ludd]

Adding moveable weight near the end of the barrel will function as a tuning device. It doesn't matter so much what material the weight is composed of, as long as it has enough mass to do the job. Obviously metal is far more dense than rubber, but as long as the rubber ring has sufficient mass, it can work. A MagnetoSpeed chronograph, which isn't all that heavy, will act as a tuner. Unfortunately, the MS isn't really very "adjustable" in terms of position on the barrel. As Mike noted, the two main issues with the rubber-based tuners are the "effective" adjustment increment, which is typically extremely large relative to threaded metal tuners, and the reproducibility of positioning them at a specific point on the barrel if they move.

To the OP, if I were in your shoes, once I had the tuner set at a point I thought was "optimal", I'd mark a fine line on the barrel at each edge of the tuner with a black Sharpie, just in case it was ever to accidentally get moved during transport/shooting. That way, you could always slide it back pretty darn close on the barrel to where it was before. If for any reason you ever found the optimal positioning needed to be changed, Sharpie marks are easily removed with acetone or rubbing alcohol.

 

[memilanuk]

FWIW, most people I know that use something like the LimbSavr or o-rings or whatever - as opposed to a more normal barrel tuner with a movable mass, like the ones that Mike Ezewell or Erik Cortina sell - seem to think that what is going on there is something subtly different - dampening the harmonics ever so slightly, as opposed to changing the tuning point.

As Mike pointed out, without in-depth studies and testing, most everything else is anecdotal at best - but when more people start getting results pointing in the same direction, maybe there is something to it.

 

[msalm]

I use the limbsaver on occasion when chambering a longer, skinny barrel. By putting the dampener on the muzzle end (outboard end of headstock), I don't get any vibrations when turning and facing the tennon.

 

[seymour fish]

FWIW, most people I know that use something like the LimbSavr or o-rings or whatever - as opposed to a more normal barrel tuner with a movable mass, like the ones that Mike Ezewell or Erik Cortina sell - seem to think that what is going on there is something subtly different - dampening the harmonics ever so slightly, as opposed to changing the tuning point.

As Mike pointed out, without in-depth studies and testing, most everything else is anecdotal at best - but when more people start getting results pointing in the same direction, maybe there is something to it.

Damping the harmonics can be demonstrated to “work”, independent of any significant mass effect. Easy to see in rimfire. Various rubber donuts lack sufficient means of dissipation

 

[Ned Ludd]

The companies that produce the rubber donuts have chosen to call them "dampeners", or some other similar name. That doesn't necessarily imply anything mechanistic about how they're actually working. I doubt the mechanism by which the rubber donut tuners work is substantially any different than a metal tuner. The only real difference might lie in where the two types of tuners are placed on the barrel. I also strongly doubt that a piece of rubber has any "dampening" effect on barrel harmonics by virtue of the material of which they're made and/or "squeezing" the barrel. They're simply functioning as a tuner and affect barrel amplitude/frequency in proportion to their mass and where they're positioned. By analogy, a more typical metal tuner could also be called a "dampener" for both practical and advertisement purposes because they effectively could be perceived to "dampen" barrel harmonics and shrink group size when properly adjusted.

 

[JMayo]

Bolt on Mid barrel tuners/dampeners are quite common in rf ARA and such. I have one. At one time it sensed to help ... It's in a box right now. But if my shoes don't improve I'll be testing it again.
Cliff Arnold makes them. Killoughs has them I believe.

 

[snert]

Hell, if I could duck-tape a banana to my barrel and get positive accuracy improvement, I'd proudly do it. Just call me "Nobody". jd

You never made fun of my duct taped sling on my Swift! Now I know why! it actually seemed to help, but being un-scientific, and knowing how much abuse I would get, i just shoot it and don't talk about it.

 

[jds holler]

My wife, who has a pretty fair amount of Okie/Hillbilly DNA in her, couldn't live a day without using duc-tape. Shoe repair, mending, package wrapping, the most ummm-- creative home decorating--- you name it. Your duc-tape sling would seem the most natural and appropriate thing in the world to her. Far be it for me to make fun of it. I thought it was perfect for your Assarikka -- Akkorissa -----Arrokossa-- oh whatever. jd

 

[wbm]

Hell, if I could duck-tape a banana to my barrel and get positive accuracy improvement, I'd proudly do it. Just call me "Nobody". jd

Love it! Thanks JD....Made me laugh this morning. I hear ya man!

 

[seymour fish]

The companies that produce the rubber donuts have chosen to call them "dampeners", or some other similar name. That doesn't necessarily imply anything mechanistic about how they're actually working. I doubt the mechanism by which the rubber donut tuners work is substantially any different than a metal tuner. The only real difference might lie in where the two types of tuners are placed on the barrel. I also strongly doubt that a piece of rubber has any "dampening" effect on barrel harmonics by virtue of the material of which they're made and/or "squeezing" the barrel. They're simply functioning as a tuner and affect barrel amplitude/frequency in proportion to their mass and where they're positioned. By analogy, a more typical metal tuner could also be called a "dampener" for both practical and advertisement purposes because they effectively could be perceived to "dampen" barrel harmonics and shrink group size when properly adjusted.

Good grasp of the obvious. Now, think Outside the box

 

[Ned Ludd]

Good grasp of the obvious. Now, think Outside the box

Please. If you want to make this far more complex than it needs to be, feel free to do some thinking outside the box yourself.

 

[seymour fish]

Please. If you want to make this far more complex than it needs to be, feel free to do some thinking outside the box yourself.

“You can lead em to water, but.........”

 

[Ned Ludd]

“You can lead em to water, but.........”

I'm not interested in playing the childish "I know more than you" game. If you have something worthwhile to add to this thread, don't be a douche, just post it for everyone's benefit.

 

[HVYDOC]

I had one in my parts box I got years ago. Thought I would try it put on my modified 10/22 I use for the NRL22 comps. It did reduce the groups but found it needed to be moved for the different ranges. If I set it to tighten up my 50 yard group my 100 yard group would almost double.
If your shooting a fixed range or had extra time to set it for different ranges it would be a benefit. ymmv

 

[#40Fan]

I had one in my parts box I got years ago. Thought I would try it put on my modified 10/22 I use for the NRL22 comps. It did reduce the groups but found it needed to be moved for the different ranges. If I set it to tighten up my 50 yard group my 100 yard group would almost double.
If your shooting a fixed range or had extra time to set it for different ranges it would be a benefit. ymmv

That is good to know. Only attempted at one range. Going to hopefully shoot a little tomorrow and see what happens.