Load nodes question

[kmw1954]

While following another topic the discussion moved to nodes for a bit and then this struck me. Seems that a load node is generally described as being or falling between a range of powder charges and mainly consist of 3 to 5 charges in a row. Say for instance 23.0gr to 23.4gr.. So my question then becomes if there is this much space or charge variance within a node then why do we spend so much time meticulously measuring and trickling powder charges? Why should it make such a huge difference if we are within a load node with the charge?

 

[Nature Boy]

While following another topic the discussion moved to nodes for a bit and then this struck me. Seems that a load node is generally described as being or falling between a range of powder charges and mainly consist of 3 to 5 charges in a row. Say for instance 23.0gr to 23.4gr.. So my question then becomes if there is this much space or charge variance within a node then why do we spend so much time meticulously measuring and trickling powder charges? Why should it make such a huge difference if we are within a load node with the charge?

Sometimes there isn’t that much of a node range and knowledge of that fact is enough to abandon a powder/bullet combo. I’ve been living this recently as I’m developing a new load for a new barrel.

Regardless of the node range, being meticulous in finding its upper, lower and median points is the goal. That allows for the greatest margin as changing conditions (temp/humidity/pressure) influence a powder’s burn characteristics and risk pushing your load “out of tune”

 

[Charlie98]

Why should it make such a huge difference if we are within a load node with the charge?

being meticulous in finding its upper, lower and median points is the goal.

As Nature Boy points out... you would have to find the exact median for the node to be able to tolerate some amount of variance, and it depends on the actual size of the window as well. If you are poking paper, or shooting steel, variations are less of a concern, but as the need for target precision rises, so the tolerance for error gets smaller.

 

[kmw1954]

This is a target out league just shot. the head is 1.5" the tale, last 5 are .5" and this is shot at 100yds. As a reference to Charlie98. Rule being cannot move to the next sub-target until the previous on has been hit.

For this I am shooting developed handloads and each powder charge is weighed and trickled. For this load I find the node is about .5gr wide from 23.7 to 24.2.. After 24.2 if falls off greatly, 23.6 still shoots good but looks out of the node as POI shifts slightly. So I have been loading and shooting to a target charge of 24.0gr. and trickle to as exact as I can visually read my beam scale.

So why should it make any difference if I am .05 grain off either way? Doesn't the node cover for this?

 

[Laphroaig]

.05 probably wouldn't matter much. If the alternative to weighing is throwing charges, you might get a few outside of your node. I typically get about +/- 1% with stick powders which would be amount to .25 grains with your load. On occasion you might get a .3.

For the competition that you're shooting I'd suck it up and continue weighing, for piece of mind if nothing else.

BTW, that's an interesting COF. I like it

 

[FROGO207]

Well I test my loads for nodes both in hot and cold weather as well as for 68*-72*. Some propellants require seperate loads when shooting at extremes. Load center of node for what you expect the temp to be when shooting. It all gets down to how much effort you are willing to exert before diminishing returns on accuracy stop you IMO.

 

[Nature Boy]

So why should it make any difference if I am .05 grain off either way? Doesn't the node cover for this?

Not knowing a few key bits of information like how you developed this load or your ability to shoot the difference it would be impossible to say

 

[kmw1954]

A decent node can be 1% wide while being 3% apart.
Example, 31.3 + 1% = 31.6 and the next node 3% further up the ladder. In between are anti /scatter nodes.
.05 is about 3 kernels of powder. Not a significant amount unless your on the edge of a node.

So my understanding of a node is a group that shoots to the same relative velocity and to the same relative POI. Correct or No? So by that definition one should be able to take the 32.3 to 31.6 node and feel relatively comfortable that they are all going to shoot the same or if loaded to 32.4 to 31.5 they should again perform the same with a buffer to either side. So that does not answer the question of .05gr deviation either side.

 

[kmw1954]

Not knowing a few key bits of information like how you developed this load or your ability to shoot the difference it would be impossible to say

Developed as most target loads are or a way that I have found that works for me and have has success with. To the next question, No I honestly do not believe that I can shoot the difference.

 

[Nature Boy]

I honestly do not believe that I can shoot the difference.

That’s really all that matters. I don’t think I could shoot the difference in a 0.05gn variation either. With that said I still load to a 0.02gn variance because that’s the limit of my mechanical balance.

To get any smaller I’d need better equipment and a razor blade to cut kernals in half

 

[kmw1954]

Yes as said I load using an RCBS 5-0-5 Balance beam and a trickler. Knowing I cannot shoot the difference or at this stage even physically see a difference I still strive to get to the center of the pointers. Could probably save myself a ton of time if I didn't, but I'm just a creature of habit and borderline perfectionist.

When loading for pistols I know for a fact that I cannot shoot the difference from a whole .01gr. either side of a target powder charge. Yet I read comments all the time about how inaccurate or inconsistent peoples powder throwers are.

I still get fascinated by reading about reloading. Be it the tools used or the procedures different people use. Biggest fascination might be just the perspectives some take towards it.

 

[kmw1954]

Volocity increases as powder is added that’s just a given although the point of impact remains stable despite the increase in powder.
I posted a very good example of this on the other thread.

As I understand the definition some also claim it is a flat spot in velocity as well.

 

[kmw1954]

View attachment 1201130
The red circled impacts are anti nodes, 31.2-31.6 represent a node where the speed increases yet the node is stable. 32.2-32.4 id another node approx 3% higher

Finally I have to admit that after following your posts for a few years now I still cannot read your pictures. Just as this one.

 

[Kaldor]

As I understand the definition some also claim it is a flat spot in velocity as well.

This is for real. With an accurate scale, and chronograph you can see evidence of this in a Satterlee test. I've seen it fall flat for velocity sometimes with charges nearly a grain in spread.

 

[JFrank]

Oh you guys are a couple of smooth operators, maybe you can figure this one out.

Maybe not

 

[Soonerpesek]

Whatever man.................
I still don't understand the theory behind a 1-shot group.......
I doubt I ever will need to, don't shoot for those teeeny tiny groups like some folks.....................
Nor am I trying to make any point other than I don't see how it works...........................




You are seating just kissing the lands and 5 different single shot charges that don't group for crap.........................what are you trying to tell me.....?

.....and according to your buddy, supposed to be 3 in the node and 1 on each side of it..................I don't see that in your pic of 3 in the node and 2 others on the same side.................

 

[kmw1954]

Oh you guys are a couple of smooth operators, maybe you can figure this one out.

Maybe not

Better yet, here is a target that should be easy to read. SO, each group where is the node? There were zero scope adjustments made during this shoot.

 

[film495]

it would be interesting to see an x,y graph dictating charge and respective consistent POI, to indicate what a node is. also, another graph to indicate charge and velocity, on a similar scale, and then lay the two on top of one another. I don't shoot fo that kind of accuracy so have no data, but the theory is interesting.

 

[Varminterror]

Looks like I’m coming into what is already a dumpster fire, but I’ll mention this:

I did some analysis on this site 2 years ago of my own load dev data from prior tests which showed an average of slightly less than 1fps per kernel for 6 Dasher with Varget as well as 6 Creedmoor with H4350 - but in a node, those kernels were not promoting any velocity influence at all over a span of ~0.3grn, whereas the WORST slope, the anti-node region, promoted 3-4fps/kernel. A kernel of either of these powders is approximately 0.015grn…

So using something like a Chargemaster which can only resolve to +/-0.1grn, that’s ~12fps average, 0fps in a node, or 48fps for anti-nodes…

THR Thread powder precision vs. velocity influence

Personally, I load with a dispenser accurate to +/-0.015grn not because it is precise (but I’m glad it is), but rather because it is FAST! I load faster with this device than I could with a conventional +/-0.1grn powder dispenser, about 3 times faster.

In simple language - loading with high resolution dispensers despite loading in proportionately larger nodes is like driving in the middle of your lane on the highway. Your car is ~6ft wide and your lane is ~12ft wide - you don’t HAVE to drive in the center, but it’s generally safer if you do. Loading with looser control is also like driving a wide load on the same highway - if I drop powder with +/-0.2-3grn resolution when a node is only 0.3-4grn wide, I have to expect my load to hang over the edges of my lane, and occasionally, I might hit something outside of my lane…

 

[Varminterror]

it would be interesting to see an x,y graph dictating charge and respective consistent POI, to indicate what a node is. also, another graph to indicate charge and velocity, on a similar scale, and then lay the two on top of one another. I don't shoot fo that kind of accuracy so have no data, but the theory is interesting.

What would be your x axis variable?

 

[Soonerpesek]

you still would not understand.

In the most civilized way I could, this is what I was getting at.
But you seem to want to insist without answering….
Once again, I don’t understand 1-shot “groups” telling me anything.
And when you don’t want to answer, you take your toys and go home….
Thanks for the help….

 

[JFrank]

In the most civilized way I could, this is what I was getting at.
But you seem to want to insist without answering….
Once again, I don’t understand 1-shot “groups” telling me anything.
And when you don’t want to answer, you take your toys and go home….
Thanks for the help….

Ok’ I’ll try this one last time just for you.

Shots 1-2-3 represent 5/10 of a grain equaling 30 kernels of powder that’s quite a bit of change yet all three shots are in basically one hole at 200 yards. And you claim that tells you nothing ?

 

[Mal H]

I have deleted a bunch of posts, maybe more than necessary, but the thread was getting ... let's say belligerent. If it's possible to keep it civil from this point on even if a little argumentative, it can remain open.

 

[kmw1954]

Here I have now been insulted, my intelligence called into question for a second time and now accused of trying to make you a fool. So as you suggested in #27 I am going to drop this. I do not need nor deserve this. Dumpster Fire is Out.

 

[Soonerpesek]

Ok’ I’ll try this one last time just for you.

Shots 1-2-3 represent 5/10 of a grain equaling 30 kernels of powder that’s quite a bit of change yet all three shots are in basically one hole at 200 yards. And you claim that tells you nothing ?

So you're telling me that 1 shot determines your load.......?
Where does, say, shots 2-5 of each charge land....?
Just me, but I would want more certification/assurance that the charge I select is what I think is the best one.....


Example:
What to do if shots 2-5 of the 30.2 charge all end up in a ragged hole of where your shot 5 is.....??