Huntsman Tuner Load Development

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AlexE
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Huntsman Tuner Load Development

#1 Postby AlexE » Wed Jan 23, 2019 7:19 pm

Following a glowing endorsement from Jason Mayers, I purchased a Huntsman barrel tuner today. I will be fitting it to a 308 ftr rifle I have been casually tinkering with.

I purchased it simply because I had a little weight up my sleeve and figured it can't hurt anything and if it does, I can just take it off.

I have already done some load development (ladder tests and groups at distance) that is giving me acceptable elevation out to 900 yards, but it still needs some fine tuning.

My question is - can I use this load as my baseline once I have fitted the tuner, or will everything go out the window, meaning I will have to start afresh with a new ladder and subsequent refinement? Will optimum powder charge and seating depth be roughly the same?

I had planned on giving some rl16 a run, so if the advice is to start afresh, it's not a huge loss, but I do have time and money invested in the load development to date, so it would be nice to build on that rather than throw it out the window.

I know tuners have been discussed extensively here (and there is some really good reading, especially from Williada!) but I am unable to find anything relating to whether a half decent load will stay that way once I have another 500g and a 6 inch tube hanging off the muzzle.

If there's any interest, I am happy to share my findings, trials and tribulations as I go along, but I'm no queen's level shooter.


Thanks folks,

Alex

williada
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Re: Huntsman Tuner Load Development

#2 Postby williada » Thu Jan 24, 2019 9:38 am

Alex, it is essential you tune your load to the best it can be to get all the ignition right without the tuner. Otherwise the tuner becomes a muzzle weight or dampener and not a tuner so as not to reach its potential. When the powder tune is correct, then attach the tuner, then it takes only small movements .002" - 005" of the tuner to enhance the tune and you are never far away from it when environmental factors change as the day progresses. Remember the barrel grows about .005" as it reaches operating temperature. I have moved away from the the 1/4 or half turns except when I want to move to a known node that suits a radical change in environment from when I set the tuner up. To me its more about managing the shock waves rather than harmonics created with the muzzle chatter and the chokes near the leade. That's what we manage for fine accuracy. The fundamental lift for compensation and also for countering torque is influenced by the weight of the tuner more so than the small movement of the variable thimble. Although a variable thimble can be used on a tuner forward of the muzzle to refine different distance settings but how successful it is depends on the barrel lift profile. That is of course related to the degree of macro lift of the barrel and bullet exit timing with the lift or downswing. There is a lot to master, or you set it and forget it based on a tight tune that you have mapped by moving the thimble forward. My preference now is to begin the forward movement of the thimble at a point close to the muzzle rather than a central point on the tuner tube forward of the muzzle. Happy days.
Last edited by williada on Thu Jan 24, 2019 4:05 pm, edited 1 time in total.

AlexE
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Re: Huntsman Tuner Load Development

#3 Postby AlexE » Thu Jan 24, 2019 11:02 am

Thank you, David - I was hoping you would chime in :)

williada
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Re: Huntsman Tuner Load Development

#4 Postby williada » Thu Jan 24, 2019 3:41 pm

Alex, I just want to add some further comments. A variable tuner extending beyond the muzzle IMO impacts on the bore size of the rifle by altering the reflected shock waves which can choke the steel by 0.0005". Not only can it alter the bore size at the muzzle but more importantly, it can alter the bore size at the leade and so essentially .002" movements in the tuner may be be close to small increments say 0.1 grain of powder or a small seating depth change. This is a generalization as there are lots of chamberings and depending whether the bullet is jumped or jammed. Beware that Quickload has a function to alter initiation pressure before the bullet moves from 3600 psi to 14,000 psi. You have to adjust for the jam setting. The only way I can truly get that setting right is with "Pressure Trace". So those doing harmonic barrel tuning maybe left in shitter's ditch with barrel times. There are huge percentage changes in peak pressure! While neck tension and atmospheric density do affect timing, it should dawn on people how important it is where a choke lies as a further pressure valve and it is only tiny for a big, big effect.

So find your natural tune first with both powder and seating depth. I might I say Frank Green saw the problem with pressure spikes in a recent post with 0.0001" diameter interference fit trying to chamber designated test rounds. How a bullet starts is a very important factor in accuracy. This is why it is essential to define the starting point without the tuner on, I repeat. We have traditionally looked at jump and powder charge to adjust timing for the expansion and contraction of steel subjected to shock waves and therefore group size. The tuner allows us to take that a little further by changing the reflection timing of the shockwaves. Large tuner movements tend to overlook good spots although tunes can be found. More on that shortly.

My experiments have demonstrated that by moving the peak pressure fore and aft it also affects barrel whip e.g. changing leade angles alters the peak pressure and barrel lift. Barrel length also effects pressure and lift. These are subtle too. Depending on the barrel lift a tuner can impact on many elements by merely changing the reflection of barrel shock waves which alter bore size. To some extent you can also time the lift to tune for distance depending on the lift profile which is also influenced by the overall weight of the tuner. Velocity may be subtly altered depending on the timing of the choke which may be suitable for adjusting for small variables in temperature. I'm inclined to think a choke near the leade slows the projectile given barrel bore size experiments but ideally I would like full ignition of the powder before that occurs. If your barrel is exhibiting a neutral compensation profile then the tuner maybe light weight. All it has to do is change the shock wave timing or interrupt it.

If we take traditional methods, powder or seating depth changes we can translate them into small tuner moves. Not a big movement because you might fall into a trough or a peak of the next node. If you are shooting peaks on the sine wave (shooter speak) in response to radical environmental changes like an upper node, the movement has to be large because you have to skip a trough node (shooter speak) and vice versa. Here the confusion has developed as to which way to move the tuner. In this sense it does not matter because you will find another node in either direction.

What I am concerned about is staying on the best node you have already selected from load development i.e. a nice, round, forgiving group and not moving to another node. Avoid super nodes as they are too temperature dependent. Or you may select a node that is least wind sensitive. Now experiment around your node by moving the tuner thimble in or out in .002" .003" increments to see where the group strings, vertical, horizontal, diagonal. How far your tuner moves depends on its thread pitch. Depending on whether there is a trough or a peak, the direction of tuner movement maybe be different if the barrel is about to downswing or upswing. Do this for yourself to learn and correct. If you get two groups forming you might be on an antinode but to be sure more shots may be required to confirm it by observing if the group is opening and not stringing. Having got the idea, paste group images on the shooting box to remind yourself of what is happening so you can correct it with the right tuner movement. Beware group shape is maintained with distance, but it is bigger. Don't mistake bigger groups for the effects of light, aerodynamic jump or shifts in the apparent aiming mark either. David. Also beware that at long range the movement of the tuner will change elevation, so the new group will form higher or lower. Let the group form while testing and then move the sights on the new group centre. Beginners might try to do this during a comp thinking the worst in elevation terms, when in fact the group centre has altered.

ps if your load development is showing horizontal on the jam back off seating depth. If the barrel leade is worn, a .025 jam migh assist concentric entry to the bore and tighten groups. A formal seating depth test is preferred after charge weight testing.

GSells
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Location: Qld

Re: Huntsman Tuner Load Development

#5 Postby GSells » Thu Jan 24, 2019 6:07 pm

williada wrote:Alex, I just want to add some further comments. A variable tuner extending beyond the muzzle IMO impacts on the bore size of the rifle by altering the reflected shock waves which can choke the steel by 0.0005". Not only can it alter the bore size at the muzzle but more importantly, it can alter the bore size at the leade and so essentially .002" movements in the tuner may be be close to small increments say 0.1 grain of powder or a small seating depth change. This is a generalization as there are lots of chamberings and depending whether the bullet is jumped or jammed. Beware that Quickload has a function to alter initiation pressure before the bullet moves from 3600 psi to 14,000 psi. You have to adjust for the jam setting. The only way I can truly get that setting right is with "Pressure Trace". So those doing harmonic barrel tuning maybe left in shitter's ditch with barrel times. There are huge percentage changes in peak pressure! While neck tension and atmospheric density do affect timing, it should dawn on people how important it is where a choke lies as a further pressure valve and it is only tiny for a big, big effect.

So find your natural tune first with both powder and seating depth. I might I say Frank Green saw the problem with pressure spikes in a recent post with 0.0001" diameter interference fit trying to chamber designated test rounds. How a bullet starts is a very important factor in accuracy. This is why it is essential to define the starting point without the tuner on, I repeat. We have traditionally looked at jump and powder charge to adjust timing for the expansion and contraction of steel subjected to shock waves and therefore group size. The tuner allows us to take that a little further by changing the reflection timing of the shockwaves. Large tuner movements tend to overlook good spots although tunes can be found. More on that shortly.

My experiments have demonstrated that by moving the peak pressure fore and aft it also affects barrel whip e.g. changing leade angles alters the peak pressure and barrel lift. Barrel length also effects pressure and lift. These are subtle too. Depending on the barrel lift a tuner can impact on many elements by merely changing the reflection of barrel shock waves which alter bore size. To some extent you can also time the lift to tune for distance depending on the lift profile which is also influenced by the overall weight of the tuner. Velocity may be subtly altered depending on the timing of the choke which may be suitable for adjusting for small variables in temperature. I'm inclined to think a choke near the leade slows the projectile given barrel bore size experiments but ideally I would like full ignition of the powder before that occurs. If your barrel is exhibiting a neutral compensation profile then the tuner maybe light weight. All it has to do is change the shock wave timing or interrupt it.

If we take traditional methods, powder or seating depth changes we can translate them into small tuner moves. Not a big movement because you might fall into a trough or a peak of the next node. If you are shooting peaks on the sine wave (shooter speak) in response to radical environmental changes like an upper node, the movement has to be large because you have to skip a trough node (shooter speak) and vice versa. Here the confusion has developed as to which way to move the tuner. In this sense it does not matter because you will find another node in either direction.

What I am concerned about is staying on the best node you have already selected from load development i.e. a nice, round, forgiving group and not moving to another node. Avoid super nodes as they are too temperature dependent. Or you may select a node that is least wind sensitive. Now experiment around your node by moving the tuner thimble in or out in .002" .003" increments to see where the group strings, vertical, horizontal, diagonal. How far your tuner moves depends on its thread pitch. Depending on whether there is a trough or a peak, the direction of tuner movement maybe be different if the barrel is about to downswing or upswing. Do this for yourself to learn and correct. If you get two groups forming you might be on an antinode but to be sure more shots may be required to confirm it by observing if the group is opening and not stringing. Having got the idea, paste group images on the shooting box to remind yourself of what is happening so you can correct it with the right tuner movement. Beware group shape is maintained with distance, but it is bigger. Don't mistake bigger groups for the effects of light, aerodynamic jump or shifts in the apparent aiming mark either. David.

ps if your load development is showing horizontal on the jam back off seating depth. If the barrel leade is worn, a .025 jam migh assist concentric entry to the bore and tighten groups. A formal seating depth test is preferred after charge weight testing.


Sensai, this little grasshopper head hurts again !! I mustn’t be that bright as I have to read your post several times over :shock:

When you say shock wave is that the donut forming type ? I’ve included a link to Varmint Al’s harmonic movie so you can hopefully explain more for us mere mortals !
https://www.varmintal.com/amode.htm

Also there is an interesting page on tuner analysis. And even more interesting is a moving showing the scope playing into the harmonics too . Which Is why I put harmonic modifiers on my scope as well.
The effects are subtle but it all adds up I guess. [-o<

https://www.varmintal.com/atune.htm

GSells
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Re: Huntsman Tuner Load Development

#6 Postby GSells » Thu Jan 24, 2019 6:12 pm

Also David , is the general rule of thumb with tuners , is it when hotter go a flyspeck out and the reverse in colder weather to speed up vibrations ?

williada
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Re: Huntsman Tuner Load Development

#7 Postby williada » Fri Jan 25, 2019 11:21 am

G’man this is complex stuff and I am not sure I have all the answers either. I can make no apologies if it’s hard to follow, it is what it is and assumes more of an engineering background as it was addressed to Alex. But plumbers should know about pressure valves and what slows flow or increases it. It’s always been my mantra when there is a big problem it must be broken down into its smaller parts to understand it and work on better solutions for total improvement when rebuilding.

I was not satisfied with the anomalies that tuning presents such as, why doesn’t low ES produce tight groups all the time? Why does successful tuning come back to small increments in powder or seating depth or both. There is something happening, the fundamental lift which largely sums up Varmint Al’s magnificent work on the cantilevered beam but does not account for the final micro tune impacted by shock waves except to say he did work on torque pinching of the bore. We also know the fundamental lift is partly satisfied in full cycles because the length of barrels and their stiffness in F Class. So we have to rely on less important vibrations and their interaction as higher frequencies for micro tuning and the compounding effects of other stress waves. In harmonic tuning there are meant to be equal divisions of the fundamental node but in reality there is other interference to those patterns so the plotted sine wave is not so rhythmic.

Years ago, I categorized the lift patterns into compensation profiles of positive, neutral and negative to look at trajectories and their grouping ability at different distances as macro tunes. Then I refined the tune within those parameters looking for reliable tune points in a given barrel lift pattern. Certainly, changing the stiffness affected tune and we came up with the stiff barrel tune and the two flexible tunes, one which approximated an harmonic tune and the other a compensation tune depending upon what the barrel wanted to do naturally. Of course, any attachment such as a scope alters stiffness, and there is consideration of the fulcrum point and its relation to bore centreline and the rifle centre of gravity which also influences the amount of barrel lift as does the dampener of fundamental lift such as a barrel weight on the muzzle. Even though things can be stiffened to give less amplitude, the gunsmith beds and attaches scopes in a manner that is stress free in its resting state to ensure repeatability of function.

For many years, I have advocated there are three major inertia points to overcome in the rifle system and that their interaction is closely linked to group size. The first major inertia point occurs on ignition, the second on bullet movement and the third on bullet exit. That poor little projectile has just broken the neck tension shackles, got to be shoved up a dark hole with its ass on fire, turned all about, and butted reflected shock waves while pushing out 1,270k of atmosphere as a heavy weight out the barrel and leaves the barrel with stripes on its back having pushed hard against the walls when emerging from the superheated atmosphere into the cool oncoming breeze. Then it suffers from the external ballistics that really gets its head nodding and its tail wagging until nutation is shaken off, leaving gravity and drag clawing at precession and yaw while it tries to spin in an epicyclical line out of trouble - and we expect it to behave - like point and shoot!

This is hardly a scene of harmony let alone true harmonic tune but one of interacting forces. Yet simple models of sine waves and resonance do give a measure of how to tune a rifle based on rudimentary understanding. But we want more.

Long ago, I also noted the similarities between the neutral compensation tune and the OCW tune and how small increments in powder and seating depth were once again used to fine tune. Then Mr long released his shock wave theory so I went about using my own pressure trace to get a handle on optimal barrel times to avoid clashing with the shock waves by way of bullet exit timing. Quick load is of course based it parameters on “Pressure Trace” and may be used to determine optimal barrel times such that the bore at the muzzle on bullet exit is minimal. I agree with that and had always crowned at the minimum bore diameter and saw merit in the reasoning. However the point that Long makes, is that the shock wave donut and there are course other stress waves, but the important one, as advocated by many, the donut travels up and down the barrel several times before bullet exit. That means it must travel down to the leade too, and open that up to change the volume of the pressure vessel and therefore its initiation pressure before the bullet moves. The reason I went for 2209 at the time in a development program was because it was a faster powder for 7 mm’s and was an attempt to get full ignition before a returning wave interfered with leade volume and ignition which I thought was a factor in altering SD. The timing of such a shock wave can also affect how the bullet engages the bore upon movement. We all know how sometimes, a tiny seating depth movement can bring a group in at times. Couper, a smart man, believes this same shockwave theory sets up the initiation pressure and the outcome is the muzzle flap. We both believe the reflected vibrations play a big role in accuracy but I think vibrations from many sources can stack up and compound their effects which may have undesirable consequences on ignition, bullet movement and exit. Can we really be sure of the speed these pulses travel then? So far the theories have tackled inertia points one and two.

If the true harmonic length such as the Purdy system works with the addition of a bloop tube and variable thimble, it does not apply to centrefire because of the shock waves overshadow the harmonic values. I have experimented with that and found that low nodal values do not apply. I also note the positive compensation node advocated by Kolbe uses node three for fundamental lift and Optimal Barrel Time advocates may use node 4 when calibrating with Quickload but that is without a tuner attached. I think node 4 has value in the micro tune of a neutral barrel. We really don’t want dramatic compensation in an across the course rifle because it has to service many distances. Yet when adding a past the muzzle tuner, I found the length of the tuner was very loosely determined by multiples of Purdy’s order from the 19th to 25th node values as merely plug in values with his method rather than nipping off the length until the groups came in by trial and error. I was not satisfied with the pure harmonic theory either having realised the Purdy prescription did not apply to high power barrels because the shockwaves cause stress waves and then there is the bullet itself enlarging the bore as it moves along it creating more pressure waves etc.

The third inertia point needs more exploration of where and how the emerging bullet makes a transition into flight. I believe the shock wave adds additional chatter to the muzzle harmonics. We know with musical theory an harmonic node of a flute for interests sake lies in the atmosphere beyond the muzzle. Harmonics is still a player. Remember that heavy weight the bullet must press against? Yes, the atmosphere approximately 1270k. That means the density of the atmosphere will also affect this node and the one before it at the muzzle if the timing is right to minimise bore size there. The role of the thimble on the tuner tube IMO is to balance lots of variables in the harmonics and the shockwaves by trial and error because of the chaos. Purdy used the node length to calculate the harmonic length of the bloop tube and hence barrel harmonic length. This would imply a fixed length for a given frequency. But we know that moving the thimble alters the reflections of shockwave frequency. I come back to Obermyer who said his bloop tube conditioned the atmosphere and perhaps it stabilized the harmonic/shockwave boundary and reduced the impact of flack particles. He looked at optimal diameter and determined length by trial and error. In my opinion that is an attempt to manage a shockwave. But the total weight also influences torque of the rifling and bag handling as well as the amplitude of the fundamental vibration of barrel lift. The length of the bloop tube (he used ones 4-5 inches) may have absorbed shock waves and may also have been linked to harmonic length. Mr Corbett has used the deep hole crown. My experiments over the years have confirmed the sight radius using iron sights was less responsible for improvement and perhaps node 3 was at work with total barrel length when desired for a given barrel profile?

The general rule of thumb for tiny movements mimicking powder or jump length: In for warmer and out for cooler if you are just wanting to alter the speed of reflected vibrations around a known node (shooter speak). This is because increasing the frequency of reflected vibration is required to retard the faster bullet if the atmosphere gets hotter and vice versa during a normal day. But note the movement is the opposite if your tuner does not hang over the muzzle.

Beware vertical might relate to a compensation tune and another node. The thimble may require larger movements depending on the lift profile of the barrel and the direction may also reverse depending on whether you a seeking a trough or a peak in the traditional sine wave test. A neutral profile barrel will benefit most from small movements. If groups form in a couple of spots then take advantage of the tuner weight and wind out to reduce amplitude using the tuner as a damper. A heavier tuner may reduce torque pinching in thinner barrels. It may move peak pressure forward and down.

There’s a lot going on and don’t forget the tuner can be left untouched once you have adjusted it. Like chasing group centre with sight adjustments you can may lose points by not allowing the group to build up with barrel moving towards operating temperature or misinterpret conditions.

If you are going to use a tuner, do the load development before it is attached.

GSells
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Re: Huntsman Tuner Load Development

#8 Postby GSells » Fri Jan 25, 2019 8:59 pm

Thanks Daivid for your contribution!!

!Peter!
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Re: Huntsman Tuner Load Development

#9 Postby !Peter! » Sat Jan 26, 2019 3:09 am

williada wrote:...That poor little projectile has just broken the neck tension shackles, got to be shoved up a dark hole with its ass on fire, turned all about, and butted reflected shock waves while pushing out 1,270k of atmosphere as a heavy weight out the barrel and leaves the barrel with stripes on its back having pushed hard against the walls when emerging from the superheated atmosphere into the cool oncoming breeze. Then it suffers from the external ballistics that really gets its head nodding and its tail wagging until nutation is shaken off, leaving gravity and drag clawing at precession and yaw while it tries to spin in an epicyclical line out of trouble - and we expect it to behave - like point and shoot!...


Hilarious :lol: :lol: , but puts the process into perspective!

And thanks again for sharing your knowledge!

williada
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Re: Huntsman Tuner Load Development

#10 Postby williada » Sat Jan 26, 2019 8:02 am

Thanks guys. I note the Huntsman tuner has a long tube. As little as 1.3" will suffice but that depends on bore size, and mach number of gas flow.

GSells
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Location: Qld

Re: Huntsman Tuner Load Development

#11 Postby GSells » Sat Jan 26, 2019 12:03 pm

I’ve just bought a Peter Larson tuner , looks the goods and it will go on a Bart 32”1-9 in of course in 280 ai . Will be interesting to see how it goes . Sorry guys I can’t post any pics of the tuner or say much about it , .

Tim N
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Re: Huntsman Tuner Load Development

#12 Postby Tim N » Sat Jan 26, 2019 3:30 pm

GSells wrote:I’ve just bought a Peter Larson tuner , looks the goods and it will go on a Bart 32”1-9 in of course in 280 ai . Will be interesting to see how it goes . Sorry guys I can’t post any pics of the tuner or say much about it , .


Coming from south oz it should be shiney
We don't rise to the level of our expectations, we fall to the level of our training. Archilochos 680-645 BC

GSells
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Location: Qld

Re: Huntsman Tuner Load Development

#13 Postby GSells » Sat Jan 26, 2019 5:56 pm

Tim N wrote:
GSells wrote:I’ve just bought a Peter Larson tuner , looks the goods and it will go on a Bart 32”1-9 in of course in 280 ai . Will be interesting to see how it goes . Sorry guys I can’t post any pics of the tuner or say much about it , .


Coming from south oz it should be shiney

Timbo , hehe, yes it is quite ! Just the lustre alone garrantes a few x’s alone , I’m sure of it ! :lol:

AlexE
Posts: 218
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Re: Huntsman Tuner Load Development

#14 Postby AlexE » Wed Jan 30, 2019 6:44 pm

williada wrote:Alex, it is essential you tune your load to the best it can be to get all the ignition right without the tuner. Otherwise the tuner becomes a muzzle weight or dampener and not a tuner so as not to reach its potential. When the powder tune is correct, then attach the tuner, then it takes only small movements .002" - 005" of the tuner to enhance the tune and you are never far away from it when environmental factors change as the day progresses. Remember the barrel grows about .005" as it reaches operating temperature. I have moved away from the the 1/4 or half turns except when I want to move to a known node that suits a radical change in environment from when I set the tuner up. To me its more about managing the shock waves rather than harmonics created with the muzzle chatter and the chokes near the leade. That's what we manage for fine accuracy. The fundamental lift for compensation and also for countering torque is influenced by the weight of the tuner more so than the small movement of the variable thimble. Although a variable thimble can be used on a tuner forward of the muzzle to refine different distance settings but how successful it is depends on the barrel lift profile. That is of course related to the degree of macro lift of the barrel and bullet exit timing with the lift or downswing. There is a lot to master, or you set it and forget it based on a tight tune that you have mapped by moving the thimble forward. My preference now is to begin the forward movement of the thimble at a point close to the muzzle rather than a central point on the tuner tube forward of the muzzle. Happy days.



G'day David,

Thanks again for your contributions. One more question, if I may -

If I'm moving in increments as small as 2 thou, what sort of distance should I expect between nodes? If I'm testing for a full revolution of the tuner (as other have suggested) at 2 thou intervals, that's nearly 20 groups I would need to shoot! As much as I love time at the range, I'm not to keen on putting 100 shots through the tube just adjusting the tuner.

Cheerio,
Alex

williada
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Re: Huntsman Tuner Load Development

#15 Postby williada » Wed Jan 30, 2019 11:12 pm

Alex, no need to fire 5 shot groups as the load development should have satisfied the statistical confidence. With the tuner in place you only need two to three shot groups because you are using a load of statistical significance. The essence of what I said was to keep you close to or return you to the best node you saw in load development. Notice how tight the first group is in the picture below? To do that requires you to sneak up in .002"-.003" movements either way of a base mark starting near the muzzle. We are only trying to mimic a small change in say seating depth to keep you on the node when temperature changes. The key is selecting the best node in the load development to also enhance it with the tuner.

Finding another node is something different and more advanced, as you can select nodes for purpose.g. least wind sensitivity, a long distance one that throws slow shots higher etc. These may require larger movements which you can track on another sine wave test such as one "Ecomeat" did for me several years ago when I was trying to convince him of the merits of a tuner. The responsiveness of the tuner depends on the barrel lift profile and as a general rule you might take .005" movements to find them or more. Larger movements might be required on whippier barrels with a lower vibration frequency. Taking a look at Ecomeat's groups you can see the groups open up with movements of the tuner and it is because they are in no man's land in the compensation points of both trough and peak and the harmonics. Also notice how the groups rotate. Some are tight and round, others least wind sensitive. If the tuner is designed properly the sine wave should be rhythmic in which case the movement distance should correspond pretty much with the distance you traveled after finding the second node. Now "GMan" should be able to tell us which nodes are used where? I did post the full reply on that a while back now that I gave to Ecomeat.

Now Ecomeat don't tell 'em, let them figure it out.

Ecomeat's Tuner Test.jpg


I will just add, the best tuners are custom made to accommodate the barrel in use.
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