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Anyone proficient with reading OCW test?

I am changing the bullet and powder combination in my 6x47. I mainly shoot PRS and I haved used the Satterlee method in the past with good results. I figure I would see if the OCW test is telling me the same thing. I had a velocity node at 41.2-42.4 the OCW i did was 100 yards. Am I still looking at a 41-41.4 window? The poi is close between the groups and I know I shouldn't get hung up over group size. Where does one think I should load to go out to a 600 yards to test?
 

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Shoot 41-41.5 in .1 increments 3 shots at distance, same target, color bullets ogive.
Something will stand out.
 
If using Newberry's system, and with only these sample shots, 41.0. Not because of group size per se, but by the pattern these shots show.

41.0 and 41.2 arguably have same POI. 42.4 and 42.6 are somewhat different, and progressively more scattered. Newberry felt many times accuracy nodes were 3% apart with a scatter node in between, a generalization that seems to fit here.

If I had no desire/ability to go higher or lower than ~41.0, I'd shoot five at 41.0 to see if it repeats and five at another load that I felt would help confirm 41.0. EG, I'd suspect 40.8 to look somewhat like 41.2 and I'd suspect another node at 42.2gr.
 
If I would call 41.6 the scatter 1.5% below would be 41g and 3% above that would be 42.2g I never tried this test until today only reading and I was just trying to confirm my thinking if I was on the right track. 42.2g will put me around the 3100fps I ran a Satterlee test up to 42.8 which put me at a little under 3150fps which is max for PRS velocity and stopped there, no pressure signs. I may load 42.2g just to see if it holds close at distance.
 
To do it properly, you need more test samples.
Like others have said, it's easier to see it coming and going
with a larger sample size, like 10 different powder weights.
I'd also go back to 40.6, 40.8, 41.0 and 41.2 just to see where that one is centered.
What bullet and powder are you using?
 
The reason this sample is small is because this is the combo I used on my last barrel before I switched to running DTAC's which I am not using anymore.
 
When I’m using around 40 grains of powder the increments between charge weights is 0.3 grains. Using 0.2 grains is not enough spread to show the width of the node when looking for 3 consecutive groups with the same POI relative to POA. Using 0.2 grains can show more than 3 groups and be hard to interpret.

This said, if 41.6 was the scatter, then 0.6 less would be the node; meaning 41.0 grains. Therefore 40.7 grains would be coming into the node and 41.3 would be leaving and going to scatter.
 

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