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Node difference

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Is there a difference between a node and a load that just shoots really good? I'm at 30.1 H4895, 105 bullets, Alpha brass 1-8t 6BRA at 2870-+ and it seems to shoot really good at 100 now to go out further when I can drive 1.5 hours to the range. ;{
thoughts?
 
Mr OCW Dan Newberry states a node will repeat at 3% charge weight difference, while a scatter node is at 1.5% difference. Observing this behavior when evaluating charge weight gives credence to the results.
1. If you are already near a high-pressure value, changing 3% up can be dangerous.

2. in 18 years of running this site, and working with multiple disciplines and multiple world record holders and national champions, I believe that this Newbury statement is not useful at all and is basically not helpful for the majority of rifles and handloaders.

I could be a little more blunt, but you get the idea.
 
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1. If you are already near a high-pressure value, changing 3% up can be dangerous.

2. in 18 years of running this site, and working with multiple disciplines and multiple world record holders and national champions, I believe that this Newbury statement is not useful at all and is basically not helpful for the majority of rifles and handlorders.

I could be a little more blunt, but you get the idea.

1. Obvious, but one can also reduce charge when developing.

2. I respect your opinion, but I also repect Dan. He has been on the range with clients around 300 days a year for many years working primarily with long range shooters to reliably hit steel targets from 300-2100yds. More of the PRS type of shooting, not BR, and in years past he worked with Chris Long to provide observations such as this.

I choose to ponder observations from many sources, and consider utilizing for my various applications as appropriate.
 
I won't carry this further except to say I believe the OCW observations will NOT help the vast majority of people. There are far better, more efficient, more repeatable, and more intelligent methods to achieve best accuracy with custom barrels.

I have seen people waste 100s of rounds of barrel life with this kind of OCW BS, when they could have achieved more with a .010" or 0.015" change in seating depth, or switching neck tension, or powder choice.

I will take it further, I have heard/seen/read no substantiation from ANY credible source whatsoever that a 3% change in powder weight achieves any highly predictable accuracy NODE repeat in multiple cartridge types, small, medium, and large. Additionally a 3% change is very significant, that would take you out of the known good load weights for smaller cartridges.

For example, a 30.0 grain 6mmBR Varget charge (good for 107s), increased 3% puts you at 30.9 grains. That is way too high if you are close to max with 30.0, and I don't know ANYone who would expect to duplicate accuracy going DOWN 0.9 grains from 30.0. No way.

I would also say that I believe the OCW mythology has deceived and mislead more handloaders than it has helped, by far. And I can tell you that OCW is cynically beloved by many respected barrel-markers, who have told me privately that they know people are wasting a huge amount of barrel life following OCW suggestions. They laugh and say "OCW is a great boost for replacement barrel orders".
 
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I would also say that I believe the OCW mythology has deceived and mislead more handloaders than it has helped, by far. But I can tell you that OCW is cynically beloved by many respected barrel-markers, who have told me privately that they know people are wasting a huge amount of barrel life following OCW suggestions.

Somehow, I never really liked the OCW theory. I tried it many years ago and followed the instructions to a T. My results NEVER gave me anything I could reasonably take to the bank.

I will stick to a .010" or 0.015" change in seating depth, or switching neck tension, or powder choice to give me something tangible.
 
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With a new powder and or a new rifle the first thing that I do is to determine what the hottest load is for a given bullet with it seated into the rifling, also recording temperature and humidity. I do this by doing a one shot per load test. In cases of this size the increment for this would be .3 gr. One of the advantages of this is that if I run into a situation where I want to do a little experimenting, I know how far I can safely go.
 
I won't carry this further except to say I believe the OCW observations will NOT help the vast majority of people. There are far better, more efficient, more repeatable, and more intelligent methods to achieve best accuracy with custom barrels.

I have seen people waste 100s of rounds of barrel life with this kind of OCW BS, when they could have achieved more with a .010" or 0.015" change in seating depth, or switching neck tension, or powder choice.

I will take it further, I have heard/seen/read no substantiation from ANY credible source whatsoever that a 3% change in powder weight achieves any highly predictable accuracy NODE repeat in multiple cartridge types, small, medium, and large. Additionally a 3% change is very significant, that would take you out of the known good load weights for smaller cartridges.

For example, a 30.0 grain 6mmBR Varget charge (good for 107s), increased 3% puts you at 30.9 grains. That is way too high if you are close to max with 30.0, and I don't know ANYone who would expect to duplicate accuracy going DOWN 0.9 grains from 30.0. No way.

I would also say that I believe the OCW mythology has deceived and mislead more handloaders than it has helped, by far. And I can tell you that OCW is cynically beloved by many respected barrel-markers, who have told me privately that they know people are wasting a huge amount of barrel life following OCW suggestions. They laugh and say "OCW is a great boost for replacement barrel orders".
Paul, I have to agree that using a general number, such as 3%, across the board of different cartridge shapes, designs and capacities, along with varying powder characteristics is not a rule I'd follow well. And, I've never given much credence to the whole obt thing, as most people agree that it only gets ya "close." I feel like I can explain this and actually, for once, I tend to agree with his repeatability of nodes and "scatter nodes" and why there is about twice as far between "nodes and scatter nodes."...although I don't agree with the generality of 3% across the board. I'll say this...I have been able to quantify, reasonably so, the value of .3 gr of n133 in a ppc and how that increment correlates to 1 mark on my tuners. It's actually very similar to his theory but with lesser values, in this case.


I'll try to refrain from using powder charge references or avoid it altogether, if you wish, but I do disagree that there is nothing to be learned here. On the contrary, I think it is a very valuable subject from which there is quite a bit to be gained. I've been looking for the opportunity to address just this, for some time.


Imagine a simple sine wave for a moment.
I think what he is saying is that a gun can be tuned to shoot small at the top and bottom of the sine wave and that the "scatter node is half way in between. To this, I do agree. You can do this with traditional powder tuning as well as with a tuner.
 
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With a new powder and or a new rifle the first thing that I do is to determine what the hottest load is for a given bullet with it seated into the rifling, also recording temperature and humidity. I do this by doing a one shot per load test. In cases of this size the increment for this would be .3 gr. One of the advantages of this is that if I run into a situation where I want to do a little experimenting, I know how far I can safely go.
Quite similar to my method. I'm a wildcatter I set up the lab and
start doing my velocity checks. I shoot three. I like to see the group
and mark down the Labs numbers with them. Some time ago I always
started at .005 off with the big stuff. I use touch for the small stuff.
When I find something the rifle and I agree on, I'll try both ends of
seating before changing charge weight. The current one I'm working
on, tightened the group going .003 into the lands. Still waiting on
decent weather to do a repeat.
 
Every shooter who reloads has his/her way of doing load development and reasons for their methods. I use the OCW method and have had success BUT...I am not a Benchrest or F-Class shooter shooting at paper for score.

My shooting is done shooting large calibers at steel targets prone off a bipod with a rear bag (squeeze type) at 1.5 MOA targets located well beyond 1000 yards. Maybe I've been lucky but, after doing a pressure test, I usually can find a good load within 50-60 rounds using a new barrel and then a small tweak after the barrel settles in. Don't get me wrong, I've had barrels that required a couple of OCW tests because they shot so well that the results were not definitive enough on the first test. Of course using components and seating depths (jump) that have shown to be successful with other shooters using that caliber also helps with getting started.

As for the 3% spread of nodes, both accuracy and/or scatter, I don't find that percentage to be that reliable for all loads for all calibers. I use the target to tell me where the nodes are not the math.

I will agree that using smaller calibers is different than the "big boomers" and the width of the node is greatly reduced, but, my opinion is that if a shooter chooses to use the OCW method he can have success with it if he learns how to interpret the results he gets instead of searching for the results he wants.
 
Node: A point, line , or surface of a vibrating body or system that is free or relatively free from motion. This is Websters definition of node. The only way i have found to take advantage of this is to alter charge weight to make the bullet exit during the relatively motionless portion of the vibration cycle. However I learned to reload in day and time when jump was not even remotely considered to be beneficial. I have never intentionally jumped a bullet in my life. I am curious to find out if bullet jump can be used to change barrel dwell time to cause the bullet to get to the motionless part of the vibration cycle( node), or does it alter group size by some other means? I am not telling anybody they are wrong i am looking for information. i think that many here think a node is another word for small group or some thing like that , but I am pretty sure it means a motionless portion of the vibration cycle of the barrel and making the bullet exit in that motionless moment in time allows smaller groups. Is bullet jump another way to put the bull in the node without using a charge weight change????
 
Node: A point, line , or surface of a vibrating body or system that is free or relatively free from motion. This is Websters definition of node. The only way i have found to take advantage of this is to alter charge weight to make the bullet exit during the relatively motionless portion of the vibration cycle. However I learned to reload in day and time when jump was not even remotely considered to be beneficial. I have never intentionally jumped a bullet in my life. I am curious to find out if bullet jump can be used to change barrel dwell time to cause the bullet to get to the motionless part of the vibration cycle( node), or does it alter group size by some other means? I am not telling anybody they are wrong i am looking for information. i think that many here think a node is another word for small group or some thing like that , but I am pretty sure it means a motionless portion of the vibration cycle of the barrel and making the bullet exit in that motionless moment in time allows smaller groups. Is bullet jump another way to put the bull in the node without using a charge weight change????

You are correct that many relate a node and load of best accuracy as the same since definitions are not consistent for everyone. And that OBT and OCW (which years later E Cortina reported as long range load development at 100yd) are the same.
 
I always wondered which is correct when fellas speak of the ocw sinne wave and how the optimum point is either the top of the wave or the bottom vs the middle etc. Now Ive learned to view optimum as a point of no vertical shifting of group centers ( within conditions of course) but how does that translate to the sinne wave ?
 
I always wondered which is correct when fellas speak of the ocw sinne wave and how the optimum point is either the top of the wave or the bottom vs the middle etc. Now Ive learned to view optimum as a point of no vertical shifting of group centers ( within conditions of course) but how does that translate to the sinne wave ?

The target curve and barrel vibration curve are different but related. Look up positive compensation and Kolbe.
 
The target curve and barrel vibration curve are different but related. Look up positive compensation and Kolbe.
Never heard of target curve but I think im pretty clear on what positive compensation is as well as exit timing results on paper , maybe were talking about the same thing or I’m just stupid but my question is where on the sinn wave is this optimum spot ? It isn’t in the middle of the wave between the low and high because that’s not stable unless it flattened out so seemingly the top or bottom if wide enough and why would one be preferred over another as long as it’s stable ?
 

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