Need Help With a Tuner

I think 4.5 to 5 ounces of moveable weight will tune a HV barrel with no problems. That is what is on my 30BR.

Keep in mind, if it is a two piece design, that means the entire thing might weigh 8-10 ounces.

That is one advantage of a one piece tuner, no unessessary weight where you don't need it.

In truth, you might ask 10 shooters and get 10 different answers. The answer I gave is based solely on my own shooting experience, and friends who shoot tuners I have built for them. The best answer is ......."whatever works for you".
 
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I don't remember the numbers, but the tuner that Butch Lambert sold for several years worked at changing tune. I think total weight was about 6 ounces, but only a fraction of the total weight was movable...maybe 3ozs. Butch might chime in to clear that up for sure. I have a couple of his old tuners at the shop, but I'm at the office and can't check the weights right now. What I have learned, is that more weight offers a wider tune window, to a point vs less weight. The difference is enough that I feel it is worthwhile if weight limits will allow on your gun. That said, even tuners that don't add any weight, but are adjustable, can and do affect tune. IME, there is a wide range of weights that will be beneficial and I've never seen a down side to 10 or so ounces on a typical br contour and length barrel. That amount of weight is not always practical though, so we have to work within rules limitations, gun handling/balance limitations, etc. If someone wants to pay for it:D, I can likely get the testing set up to put quantitative numbers to the amount of weight that it takes to yield the best return for a given barrel stiffness. I keep going back to that term, and I hope we can all see why. Stiffness, not contours, give a more precise way of comparing apples to apples.
 
FBecigneul said:
Hey mwezell:
I just had a thought and that was; has anyone tuned a fluted barrel that you can think of?
Click to expand...

I have put them on a couple. I couldn't tell much if any difference in how they tuned vs a non fluted. As I mentioned previously though, I've also used Boyd's idea of cutting a "hinge point" in the barrel around it's circumference that was about 8-9" behind the muzzle, 2" long and .125" deep, nominally due to the taper of the contour. It made a quite noticeable difference in how it tuned. I'm sure fluting has some of the same effect, just not as much due to simply not losing stiffness as fast as the "hinge point" method. But yes, if we're thinking along the same lines, it does seem to have some merit, IMO.
 
I have begun using a Gene Beggs tuner for my 30BR. I am being coached by Rod Brown and I have been successful with this barrel and a 6ppc. I could
not get all of the horizontal out of the 30BR before I used the tuner. If I changed the seating depth or the powder charge the groups would get bigger.
Using the tuner I got the 30BR to shoot in the high zeros, 5 shot groups at 100 yards. My 6ppc Bartlein barrel would shoot in the high teens before I got the tuner. After the tuner it is shooting 5 shot groups at 100 yards in the zeros. The tuner can take out the horizontal. Thanks, Rod.
 
a short tuner story

Shooting 1000yd benchrest for some years I decided to go to the NBRSA Texas State 1000YD match and use my weak middle contour w/intigrated tuner 6 Dasher,The winds were up so I was studying the wind through my scope and getting ready to shoot and my buddie asked me if my gun was in tune and I said well sure{ I hope},I should not have any vertical. When the group came back I could not have been more satified ,it was awsome.I almost framed it on the wall . It was 23" wide and centered almost perfectly. The reason I was so thrilled was that it was so flat you could lay out a straight edge litterally and catch all 5 holes, my buddie came up and looked and said well it seems your in tune by your description of no vertical but your wind reading sucks lol. I agreed so I went from watching flags to watching mirage on the next relay. I knew my tune was dead on so I was really pumped but the winds were up at bit so it was not exactly dasher weather ,but it still shined. When the target was back it was 3.1" and new range record as well. I was still more proud of the first target with a 23" group lol.

Tim in Tx
 
With regard to tuners adjusting for environmental effects;
The literature indicates most folks using tuners with good results have characterized their barrel-tuner combination and have graphs of tuner adjustment vs temp.

I think a more useful metric is Density Altitude. This has a loose correlation to temp, but D.A. is better. I check density altitude with my smart phone app before I practice and after I finish. I record D,A. as well as temp. in deg C. There are two private airports within a couple miles of our range. I think temp is effectively as good as D.A. but, Hey! I can read both!

Over the winter to summer climate changes the Density Altitude can vary from -1000ft to +2000 ft. The actual altitude at the range is 170ft! Also, the temp. varies about 2 deg C to 35 deg C.

Along with the multitude in environmental effects in D.A. there are more than trivial ballistic changes. A well adjusted tuner not only effects a shot much the same way adjusting powder weight, jump and other things like seating force, but it can also adjust for "positive Correction." This is when the bullet leaves the barrel at different times with respect to the ideal time, but the barrel points slightly up for a slower bullet and slightly down for a faster bullet. The end result is the normal, fast and slow bullets all impact at the same place. You will have to adjust the tuner for different Density Altitude, temp or whatever indicator of environmental conditions to maintain this positive correction.
 
Yep, me!

FBecigneul said:
Hey mwezell:
I just had a thought and that was; has anyone tuned a fluted barrel that you can think of?
Click to expand...

This is my rifle in Australian Sporter configuration, 9lb. I fluted the barrel with a 7mm ball nose milling cutter, .25mm per pass at 150mm/minute, 3000rpm with flood coolant.

It is a 22 Beggs, and the tuner works a treat.

Rob.
 

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Question from West Texas Tunnel

Judging by the number of views and responses to this thread there is great interest in tuners among the centerfire shooters. My experiments began back in 2003 after completion of my 100 yard test tunnel. At last, I had a wind free facility to test in. It's been interesting. :p

In recent weeks, I've done a lot of tuner work in the tunnel and promised to share with you here on BR Central what I've discovered. My question is,

Would you prefer to continue with Hunter's original thread, or would it be better to start a new thread entitled, "?" What do you think?

Gene Beggs
 
Gene,
Let me start by thanking you for generously sharing what you've learned. Early on that's one of the things that impressed me about the people in our sport. Also, to this point I've found the things I've learned from you worked very well in my applications. I'm very interested in what you have to say now. My suggestion would be to start a new thread as this one may not get as much attention. People may think they've already seen everything this thread has to offer. Either way, I'll be eager to read.

Rick
 
Gene, post wherever you like. I do think that a new thread would be best after this much time but I'll find it, as I look very forward to hearing your findings.
 
At last, the final piece of the puzzle!

Okay guys, after a good night's sleep and plenty of black coffee, I believe I'm ready to tackle this. What I would really like to do is keep my mouth shut, slink away and hide because I've been wrong about something for years. :rolleyes: Yep, completely bassackwards!. :eek:

Thanks to Rod Brown, Richard Brensing, Mike Ezell and others, we now know how to tune our rifles by making .001 adjustments during the first match of an agg. Most of us had been making way too big of adjustments and going through in-tune positions, but like Mike said, "Sometimes we got lucky." Getting in tune is one thing; staying in tune throughout the day is quite another. That's where most of us have been confused! :p I'll try to explain.

First a question; what makes our rifles go out of tune as the day progresses? Simple! Change in atmospheric conditions due primarily to increases in temperature. As temp goes up, weight of the atmosphere decreases, the bullet encounters less atmospheric resistance as it travels down the bore and begins to exit the muzzle too soon. We can correct for this in one of two ways; (1) reduce the load (2) move the tuner to increase the barrels frequency. But if you're using a tuner, which way do you go; in or out? That's the sixty-four-thousand dollar question and something I've been mistaken about for years! :eek:

Yep, old Beggs and most others have always believed that turning the tuner in toward the breech raises the barrel vibration frequency; turning it out toward the muzzle decreases it, BUT THAT'S WRONG! It's exactly the opposite! I'll tell you how I discovered it. :rolleyes: :cool:

Several months ago, I began wondering exactly what frequency our barrels were vibrating at. Having no sophisticated instrumentation, I thought maybe someone that tunes pianos and other stringed instruments might be able to help. Lo and behold, I found a friendly music store owner who had just what I was looking for! :) I grabbed one of my sporter barrels, screwed the tuner discs all the way in to the end of the threads and hot-footed it back to the store! By holding the barrel between the thumb and forefinger at the right spot and striking it with a drummer's stick, the barrel would ring like a bell. Placing the pick up near the barrel showed it was vibrating at 1000 hertz.

I wondered how much the frequency would change if I screwed the tuner 'out' two turns toward the muzzle, expecting it to lower the frequency and was shocked to find this INCREASED the frequency to 1020 hertz! I couldn't believe it! That explained why I had trouble keeping the rifle in tune as temp increased twenty to twenty-five degrees from the first match of the day to the heat of the afternoon. I was going the wrong way! :rolleyes:

Well guys, that's about all I've got to say for now. I'm not much of a writer so bear with me. I don't mind owning up to mistakes when I discover I've been wrong about something. That's how we learn. :p I hope this post generates more lively discussion.

Later,

Gene Beggs
 
It would be

very interesting to see if this holds true for all tuners. Behind or in front of the crown.
I wonder if we are just scratching the surface of how a tuner really works. I applaud your efforts Gene.

Richard Brensing
 
Gene,
IMO when you did your music store test, you were looking at the wrong thing. What you were measuring was the natural frequency of the barrel. If you look natural frequency up, it is the frequency at an object vibrates when it is not driven or damped. When you screw that barrel into an action, that is part of a rifle, and fire the rifle, the barrel is being seriously driven. If I may, let me suggest a better model, an old clockwork driven metronome. As you know, on one of these, as you move the weight away from the pivot, the swing rate decreases. Many times we get caught up in trying to explain why a thing happens when we would be better simply gathering data, and saying when I did this, that happened.
Your friend (who wishes he had a tunnel)
Boyd
Added later: If I understand what I have read, from you and others, accuracy nodes repeat as a tuner is gradually adjusted in one direction. What this means is that if you are out of tune, you can go either way to get in tune, but perhaps not by the same amount. I think that this is all about catching the muzzle in its optimal position as the bullet exits. We can get to the same position in the cycle by either advancing or backing up.
 
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