starik tube/tuner

[dontshootcritters]

Hi guys

Id be interested to hear from anyone who has tried and purchased on of Guy Stariks bloop tubes/tuners. I see they are now carbon and admittedly they look to be very well made and he has a well set out web site which is impressive. He has some big names giving the thumbs up but Id be interested to hear from others as they are a healthy hunk of $$ and the foresight will need to be increased as a result of any additional length to the barrel too

Thanks in advance

[patriot]

I use BeeStings so I can't comment directly. They allow the rifle to be tuned to the ammo rather than having to find ammo for a particular rifle. Can extra weight be added to the Starik tuner?

Mark

[dontshootcritters]

Hi Mark

I had a look at the Beesting over the weekend and they need to update their webb site. It must be nearly 10 yrs old and the video on Youtube is very dated!
The workmanship looks to be very nice. Not sure if either is better than the other?

[gstarik]

Hi Mark,
I don't think you can tune the ammo to the rifle. A tuned rifle will shoot better with any ammunition. You can't make a bad ammo shoot well,but you can make it shoot better. Once the rifle is tuned for positive compensation, it will shoot better with every ammunition. A tuned rifle will allow you to get the full potential of your system. My carbon tube is light because I beleive that the weight I use,will give the best results,and minimize vertical stringing.The other feature in my bloop tube,is that the length of each tube is calculated by odd harmonics to the length of barrel,so every tube is actually custumade.
Guy.

[up2spec]

It makes you wonder why aren't the match barrels sold by the big 3 manufacturers tuned when they leave the factory? They are all designed for the same purpose to use the same type of ammunition of about the the same speed. Are Anschutz, Walther and Feinwerkbau making their barrels the wrong length?

[Tim S]

It makes you wonder why aren't the match barrels sold by the big 3 manufacturers tuned when they leave the factory? They are all designed for the same purpose to use the same type of ammunition of about the the same speed. Are Anschutz, Walther and Feinwerkbau making their barrels the wrong length?

I'm not sure that it does. A large number of shooters, possibly a majority, won't gain much, if anything, from a tuner because their hold/aim/shot execution is not good enough to show the difference. For many shooters improving their position and technical skills will deliver far greater improvements, and some simple ammunition testing will usually provide consistent 10-ring accuracy, which even in these days of decimal scoring is enough for many.

There is also the matter of cost. If you want the factory to play around with barrel length, retesting, removing, rechambering, more testing, expect to pay a lot more for a rifle. Many intermediate level shooters would balk at paying that much more, just for shaving their groups a fraction, compared to say paying a small premium for a selected barrel.

[patriot]

Hi Mark,
I don't think you can tune the ammo to the rifle. A tuned rifle will shoot better with any ammunition. You can't make a bad ammo shoot well,but you can make it shoot better. Once the rifle is tuned for positive compensation, it will shoot better with every ammunition. A tuned rifle will allow you to get the full potential of your system. My carbon tube is light because I beleive that the weight I use,will give the best results,and minimize vertical stringing.The other feature in my bloop tube,is that the length of each tube is calculated by odd harmonics to the length of barrel,so every tube is actually custumade.
Guy.

Guy,
Are you proposing one lot of ammo averaging 1040 FPS and another 1070 will have the same harmonics; same tuner point? Atmospheric temperature and pressure won't change the harmonics? Barrel Profile or material? Stock material, bedding, receiver torque, or contact points? The additional weight of a front sight? How is it simply moving the weight on a tuner a few thousands can change the tune yet these other variables have no effect? If it can be calculated precisely, why even have an adjustable weight.

From my limited testing there does seem to be narrow tune points, good for one ammo lot, and broader points where several lots or brands perform well. But on two very similar rifles those points are far apart. How is it changing my shoulder, cheek, and sling pressures can change the ring the rifle makes? I honestly believe I sometimes hear when the rifle is in tune and see the results at 100. Wouldn't adding or reducing tuner weight, or any weight near the muzzle, slow down or speed up the vibrations; changing the time band of positive compensation?

I would be very interested in any test data you can share that supports the theory.

Mark

[gstarik]

Mark,
If the rifle is tuned for positive compensation, it will shoot 1040fps ammo and 1070fps ammo to the same poi.The rifle will be tuned than for any ammo varies from 1040-1070fps. Usually I can find 2 sweet spots
Where I get full positive compensation. If you want to understand the topic more thoroughly, go to varmintal.com,there you will also find all the scientific data needed.
Guy.

[kevin nevius]

All:

I thought I would add a thought or two, just my opinion here (for what it's worth):

There seems to be two schools of thought regarding the "tuning" of barrel vibrations (with regard to the RF sports). Tony Purdy pioneered the idea (and analysis) behind the use of harmonic resonance, based mainly in the overall length of the system - probably very similar to the theory Guy is using. The other theory is the manipulation of mass (which is the basis for most of the tuners used in BR competition today). Both are very valid based on my personal testing, but my experience with each method was oftentimes not repeatable (the sweet spots found in one session were not there or moved in later testing to validate the findings).

I am not sure I fully buy into the theory of positive compensation (different velocities impacting in identical positions on the target), but I do test with ammunition lots of varying speeds to try to find common sweet spots between them. If you can find them, I have found these positions to be more forgiving and therefore preferred.

In my very humble opinion, it makes sense to me that the best extension tube design is one that would allow incremental positioning parallel to the barrel axis (the entire assembly)........incrementally shifting mass and changing overall length at the same time with a locking system that would allow repeatability once a sweet spot was found.

Just thinking out loud, and not trying to rain on anyone's parade. I have heard great things about this product, and look forward to trying / testing one at some point in the future.

All the very best,

kev

[gstarik]

Kevin,
I know you are very knowledgeable and experienced and I appreciate your input.
I use Tony Purdy (prx) to determine the length of every tube I make. I use on my tubes the combination of the 2 schools,so every shooter can use the tuner,and the length of tube is already Calculated by me regarding to barrel length. When I find the sweet spot it's repeatable by means of shooting differnt speeds to the same poi. However, size of groups can never be repeatable and will never be...
Still,a tuned rifle will always shoot better than untuned rifle. When testing from a fixed bench you will never get positive compensation. You need the rifle to recoil. That's one of the reasons that many shooters seem to have better groups shooting from the shoulder than from a fixed vice.
Guy.

[patriot]

These discussions are interesting and I would bet Kevan's experience and rigor has taught him much. If the smallbore system were that simple, deterministic where one or two variables were responsible for causation, it would take much of the mystery out of this crazy game we all love. Tuning for 50 is much easier than 100, what distances do you use for testing? Do you have access to a lab similar to what Landy built where you can control the environmental factors? Maybe I'm a bit slow, could you explain how these articles make the point that the other variables are not involved? Geoff's tests were not off the shoulder, yet they seemed to show positive compensation.

I haven't spent much time testing the theories lately; been pushing for the finish line at work. I even set aside my obsession with using AI (neural nets) to determine which variables are predictive. Maybe in a year I'll pick it back up ... or maybe I'll just go kayaking.

Mark

http://www.geoffrey-kolbe.com/articles/ ... barrel.htm

http://www.varmintal.com/a22lr.htm

[KennyB]

Like Kevin, I don't completely buy into the Positive Compensation idea - if I understand correctly, one implication is that you would need a different point of tune for 25 yards, 50m and 100 yards. I don't find this to be true and my rifles shoot equally well at all ranges with only one point of tune. I also haven't found any need to change the tune when shooting different batches of ammunition - which again doesn't match up with the compensation idea.

I'm not convinced by the PRX theory either - I've not had any real success with tubes cut to the appropriate lengths either in Aluminium or carbon fibre. I can't see how the MASS of the tube isn't relevant, it just seems counter-intuitive to me...

I DO know that for both my barrels there is a point at about 9/10ths along them where the vibrations are significantly less - not exactly a node but a point where the strongest two frequencies pretty much disappear, resulting in a much smaller amplitude as only the higher frequencies are present there (according to spectral analysis of the recorded waveform).
Unfortunately I haven't yet been able to measure the vibrations at the muzzle with a tuner attached but I think that would be most informative.

I AM convinced that tuners work - after selecting my current batch at Eley, I repeated the 40 shot test without my tuner and the group was 3mm bigger and the gun score was 3+ points worse. Not exactly statistically significant but makes you think...

From what I've seen of Guy's Carbon tuner tube, it looks nicely made and evidently does the job for Matt Emmons and many others.

Ken.

[patriot]

There is a fairly simple test to prove compensation. Shoot a number of 10 round groups with a 30+ FPS spread through accurate chronographs near the rifle muzzle and at 100 yards. Calculate the vertical spread due to gravity based on the flight time difference between the fast and slow rounds, factoring in the chronograph error. If you shoot vertical groups smaller than the calculated spread, the minimum possible from a stationary node, then compensation is taking place.

Mark

[BigAl]

There is a fairly simple test to prove compensation. Shoot a number of 10 round groups with a 30+ FPS spread through accurate chronographs near the rifle muzzle and at 100 yards. Calculate the vertical spread due to gravity based on the flight time difference between the fast and slow rounds, factoring in the chronograph error. If you shoot vertical groups smaller than the calculated spread, the minimum possible from a stationary node, then compensation is taking place.

Mark

If compensation is to work correctly surly the muzzle must be at some other point than a node. As I understood the theory behind compensation it relies on the fact that a slower traveling bullet exits the barrel at a higher point in the vibration cycle than a faster bullet. By definition that could not happen at a node of a standing wave. Although I accept that tuning a batch of ammunition for a node can minimise group size, I find it hard to beleive that the amplitude of the barrel vibrations in a good smallbore match barrel, with a diameter of around 25mm/1", could be enough to provide significant compensation, even at or near a maxima of the standing wave. I think it is far more likely that for a prone/positional shooter the compensation effect is due to the variation in the bullet exit in the recoil pattern. This would account for the often seen fact that groups from the shoulder being better than from a rest, well at least for the elite level shooters.

Alan

[gstarik]

Few years ago, I was invited by Dr. Jeffrey Colb to his company- Border Barrels. I stayed with him few days testing for positive compensation with his device. Jeoff,built a new test bench which recoils up and gave almost the same pattern of vibrations like I have in my prone position. When adding between 200-260gr.to the muzzle,we got positive compensation on his device. When we added more weight,the vibration at the muzzle looked like almost a straight line and we couldn't get the bullet to exit at the upper slope(which needed for positive compensation). There I got the idea,to built a bloop tube with an tuner which will be light enough to get positive compensation. The Carbon Tube is about 220gr,allowing the bullet to exit at the upper slope. I can tune every barrel with the Carbon Tube to shoot batches with 35fps difference in speed,to shoot at the same vertical point on the target at 50m. Matt Emmons,and many elite shooters in the world using the Carbon Tube tuned their rifles easily for positive compensation. I'm totally confident in the theory scientifically, and practically. Using the prx on my tubes gave even better results,and made tuning easier.
I think that the combination of the mass in front and length of tube makes this tube so successful.
Shooters in a high level can tune their rifles,shooting from the shoulder. Others,can tune from a bench,but in my opinion,the results of tuning will be different, due to differnt recoil.

[patriot]

What length and diameter barrel did you use in the test? Was it mounted in the stock, barrel clamped in the device or ...?

Nothing scientific, but I'm continually surprised how well the thinner 1407 barrels shoot which leads me to wonder if the barrel profile couldn't enhance compensation.

Mark

[gstarik]

Mark,
I wrote Dr. Jeffrey Colb about the picture of his "rigid" bench in his article, and that's what he wrote me back:


"You imagine that the barrel clamping rig was 'stiff' and did not move under recoil, but that was not actually true.
I am attaching two images. The first one is the barrel clamp rig with a barrel in the clamp. The barrel clamp sits on a plate, which is attached to a rigid concrete block via three legs, two at the back and one at the front.

The second image is rig-under-recoil and this shows what happens when the rifle is fired. The recoil pushes the barrel clamp back. This causes the plate underneath the barrel clamp to bend downwards, allowing the barrel clamp to rotate backwards slightly. The result is that the front of the barrel flips up, just as it does when you are shooting.

I developed the other bench which recoils later on because I wanted a rig that would allow the rifle to recoil just as it would if a person was shooting it from the shoulder. The barrel clamping rig does not reproduce what happens when the rifle is shot from the shoulder - though it does allow the barrel and action to 'recoil' after a fashion.

The point is that the barrel clamping rig is not rigid, it does flex under recoil allowing the barrel to flip 'up' as it does when shooting from the shoulder (but not in exactly the same way as it does when shooting from the shoulder) and you can get 'positive compensation using such a rig.
Regards,
Geoffrey."

I will try to upload the pictures of the rig later on...
Guy.

[markgrabowski]

Guys, could someone tell me what is the outside diameter of Guy's tube near the exit?
Thanks!
Mark

[gstarik]

24mm

[markgrabowski]

Thanks, Guy.

Say, I do have a few questions for you about the system. I do shoot mainly NRA prone, with several stages using a scope. Normally I would take the front sight off while using a scope, or on other rifles, I would put the front sight on a bottom of the barrel 6 o'clock additional mount, to keep the weight on the barrel end the same. How do you handle the front sight when using a scope?