Tuners - what you're missing

[Marksman63]

Set and forget is just like shooting the same load all day, every day...Sometimes it works better than others. Conversely moving the tuner is just like adjusting the load to keep up with tune changes. I'm of the belief that tune changes are inevitable as powder burning is a chemical reaction and all chemical reactions are temperature dependent. If you have a load that stays in tune better than others, you'll simply need to move the tuner less often.

There are lots of ill conceived notions about tuners. I'll say this, as I've said it many times but it's still very true. The most common two mistakes with using a tuner are moving it too far and moving it too often. There are days when I never move the tuner and there are days I move it by a mark or two. Each mark is .001" of an inch. No doubt, enough to affect tune considerably.

Just as weighing each kernel of powder is important to methodically working up your best load, so are even fractions of a mark on the tuner...but being very methodical with either, is the key to success. Grabbing a tuner and twisting randomly is akin to randomly throwing powder charges and seating bullets a full turn of the seater top(or some other random amount). You can luck into something either way but I know no one that thinks either is good nor methodical.--Mike

I have tried to get a rule/correlation between tuner marks and temperature, i.e 1mark/5*F. I could only understand that I have to screw it when temperature rises and viceversa. But a proper confident level requires too many shots. Mine is a EC tuner

 

[Ned Ludd]

Set and forget is just like shooting the same load all day, every day...Sometimes it works better than others. Conversely moving the tuner is just like adjusting the load to keep up with tune changes. I'm of the belief that tune changes are inevitable as powder burning is a chemical reaction and all chemical reactions are temperature dependent. If you have a load that stays in tune better than others, you'll simply need to move the tuner less often.

There are lots of ill conceived notions about tuners. I'll say this, as I've said it many times but it's still very true. The most common two mistakes with using a tuner are moving it too far and moving it too often. There are days when I never move the tuner and there are days I move it by a mark or two. Each mark is .001" of an inch. No doubt, enough to affect tune considerably.

Just as weighing each kernel of powder is important to methodically working up your best load, so are even fractions of a mark on the tuner...but being very methodical with either, is the key to success. Grabbing a tuner and twisting randomly is akin to randomly throwing powder charges and seating bullets a full turn of the seater top(or some other random amount). You can luck into something either way but I know no one that thinks either is good nor methodical.--Mike

One difference between an F-Class match and BR is that you're not directly seeing a "group" in F-Class. The best you can do is to look for a trend over several shots using the shot marker. In addition, the wind conditions can further compound the difficulty of interpreting how the rifle is actually "grouping" in the context of the typically longer wait between shots. That doesn't mean it's impossible and you certainly could change the tuner setting during an F-Class match, but I don't believe very many F-Class shooters using tuners actually choose to do it. If you do, you just have to know how the change you have made is going to affect the grouping, as Mike pointed out.

 

[gunsandgunsmithing]

One difference between an F-Class match and BR is that you're not directly seeing a "group" in F-Class. The best you can do is to look for a trend over several shots using the shot marker. In addition, the wind conditions can further compound the difficulty of interpreting how the rifle is actually "grouping" in the context of the typically longer wait between shots. That doesn't mean it's impossible and you certainly could change the tuner setting during an F-Class match, but I don't believe very many F-Class shooters using tuners actually choose to do it. If you do, you just have to know how the change you have made is going to affect the grouping, as Mike pointed out.

I think you hit the nail on the head. It's certainly more difficult to tune, by any method, when you can't shoot a group or two, have no sighters and or have to wait between shots while the wind is blowing. Thing is, it's the same for tuning by any method. A mass on the end of the barrel makes it vibrate at a lower frequency. This, by definition, means the nodes are further apart and slower. Hence, a wider tune window, even if you never touch it.

 

[gunsandgunsmithing]

I have tried to get a rule/correlation between tuner marks and temperature, i.e 1mark/5*F. I could only understand that I have to screw it when temperature rises and viceversa. But a proper confident level requires too many shots. Mine is a EC tuner

Question...have you tried the same method without a tuner with any success?
I've done what you're talking about but was not 100% reliable. I'll say this though...first, it wasn't bad at all, just not 100%. Second, 5 degrees is only enough to seriously take it out of tune unless it was on the edge anyway.
Not a bad thing...if you can keep it there. That's where they often shoot best but won't agg. The biggest temp swing I've shot in, that I can remember was 45 degrees. I moved my tuner 2 marks over the entire day.

 

[Marksman63]

Question...have you tried the same method without a tuner with any success?
I've done what you're talking about but was not 100% reliable. I'll say this though...first, it wasn't bad at all, just not 100%. Second, 5 degrees is only enough to seriously take it out of tune unless it was on the edge anyway.
Not a bad thing...if you can keep it there. That's where they often shoot best but won't agg. The biggest temp swing I've shot in, that I can remember was 45 degrees. I moved my tuner 2 marks over the entire day.

Without the tuner I use QL to tune my load with temp when lucky to foresee it

 

[gunsandgunsmithing]

Without the tuner I use QL to tune my load with temp when lucky to foresee it

Awesome! How much does it say to change your load for a 5 degree temp change? Also, what case, bullet and powder? Thanks!

 

[Dusty Stevens]

Without the tuner I use QL to tune my load with temp when lucky to foresee it

I know I'm not the only one that would like for you to expound on this subject.

 

[Marksman63]

I thought it were almost normal.
Arrange my OCW load, input it in QL, shot the simulation, shot it at range and measure speed and temp, calibrate QL through measures speed and temp, get your powder load according different temps.
Lapua Palma case, Berger 200.20X, VV-N140

 

[tn6br]

Too many other variables play a role in tuning besides temperature for your method to be full proof. imo

 

[Marksman63]

Too many other variables play a role in tuning besides temperature for your method to be full proof. imo

Yes, but this is what I can manage with QL. Other variables through experience

 

[tn6br]

Yes, but this is what I can manage with QL. Other variables through experience

Experience is worth a lot!

 

[gunsandgunsmithing]

Yes, but this is what I can manage with QL. Other variables through experience

I'm still curious how much QL recommends changing the load for a 5° temp change. That's a sincere question, btw.
I've had good results correlating group size and shape to tuner setting, then carrying that information over to how much a mark on the tuner means in powder charge change. I'm not a big advocate of ocw tuning, mostly because its entire basis seems to imply that tuners don't work. To which, I know better. That's not to say that your method of tuning doesn't work for you. Perhaps there can be validity to both.

 

[Marksman63]

I'm still curious how much QL recommends changing the load for a 5° temp change. That's a sincere question, btw.
I've had good results correlating group size and shape to tuner setting, then carrying that information over to how much a mark on the tuner means in powder charge change. I'm not a big advocate of ocw tuning, mostly because its entire basis seems to imply that tuners don't work. To which, I know better. That's not to say that your method of tuning doesn't work for you. Perhaps there can be validity to both.

I cannot currently run a simulation being away from home, however I guess it’s more or less 0.25gr./5*F (for my .308 F/TR load).
Why OCW does not work with tuners? I think a tuner influences the barrel’s harmonics which are correlated with barrel’s lenght. Therefore, IMHO, OCW would depend on a tuner.

 

[Kurt Blasser]

Work up a load (tuner installed) without moving the tuner. After you have a good load you can move tuner a mark at a time to tweak out all the potential of that load in any given condition. It's stupid easy and almost like cheating.

What distance do you do the tuner adjusting?

 

[Kurt Blasser]

Yes, but as you've found with seating depth, you're close.
1-2 marks on my tuner is typical from a 100 to a 1000 yard tuner setting. I shoot short range but do some testing at both. Thing is, tuners can't work at one distance and not the other. They do work well for long range but the wind is such a big variable as is seeing your bullet holes. With good notes, you can set them based on conditions, mostly temps, but sights are best for sure. There isn't a down side though.

Mike, What distance do you recommend testing tuner adjustments?

 

[tn6br]

What distance do you do the tuner adjusting?

You can move the tuner whenever at whatever yardage. It could change from one relay to the next.

 

[6BRinNZ]

Mike, What distance do you recommend testing tuner adjustments?

100yards is a good distance to see the effect on group size shape and poi.
The principles here will work at longer distances as well.

 

[Kurt Blasser]

I'm interested in what we are looking for in the testing of a tuner. I shot a series yesterday at 100 yds. I can incorporate the targets later. I could notice almost a circular pattern of the groups of three going clockwise as I turned the tuner outward 1/8ths of a turn. Some of these groups were smaller. Some of the groups while small, were not the smallest but had significantly less vertical. What should I be looking for? Do I want the one that is closest to the POA? They would rotate away from the point of aim.

 

[6BRinNZ]

For F-class purposes I look for a shrinking of group size and a flattening of POI from one tuner setting to another.
Watch out that as you reduce vertical you don't introduce horizontal.
IME (which is limited) you should see a series of settings relatively close together that have a similar POI reduced vertical and are small on average although not necessarily the smallest shot. I pick the middle setting of these. I am finding that this setting will hold true over a variety of powder charges and seating depths.

I'm sure for other disciplines the above would not be appropriate.

 

[Kurt Blasser]

Tuner sheets. May be a bit hard to interpret. Shot on a shotmarker system, all on one real paper sheet. First 8 were aimed at the cross, and second sheet aimed at the circle.