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Selecting powder nodes from chronograph/SDs/flatspots - What am I doing wrong?

While I admit I am more of a Internet HM than a match HM I am a long time data geek and have really began to wonder about the relationship between barrel harmonics and flight ballistics and how they correlate.

anyway I did a thread a few months back on the effects of annealing and noticed that higher velocity did nit necessarily mean a higher point of impact. Whether this was shooter induced error or due to barrel harmonics I cannot say. I have a Shot Marker system on order so I will be doing more testing on this this summer.

Case Prep, Velocities and Point of Impact

 
@JimSC in the name of the topic of this thread, which was drilling down on velocity flat spots, what was your update on your load when taken out to distance?

The group shots where you showed <0.5 MOA but with poor ES, did those give a good group or vertical at distance? Did your scores go up or down in proportion to distance, not counting missed wind calls? Did you still see the "WTF flyers"?

Some nodes are tolerant of a bigger SD and some are not. For example, if the node is compensating in our favor, a fast shot comes in below a slow one. Depending on your luck, that effect balances with the velocity stat and the performance is still good at longer distances. But, the opposite is also true, meaning if the node we selected creates a proportional vertical spread at distance, then we either correct the root cause of the velocity spread or move to a different harmonic.

It is only my own opinion based on participating in not just small arms, but heavy weapons and artillery that it is better to know all the characteristics (Velocity and Groups) than it is to just know the groups (trajectory).

I can easily say that many folks who don't even own a chronograph are capable of shooting high performance groups at any distance, but then it is also my opinion that they learned to do so at greater shot counts than those who set out with both group and velocity in mind from the beginning when the context is greater than 600 yards. The whole point of Mike's thread is really about how much emphasis and resource should be put on the velocity and getting the overall tune with the fewest shots wasted.

ETA: It is also my opinion, that unless you already know the territory from a similar barrel and chamber, it isn't enough to just know the velocity stats cause those don't expose the group harmonics. Can you just shoot the groups, yes, but if you only test at short range you run the risk of finding out you needed a different node due to the velocity stats at that group node hiding the vertical issue you only uncover at range.
 
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@JimSC in the name of the topic of this thread, which was drilling down on velocity flat spots, what was your update on your load when taken out to distance?

The group shots where you showed <0.5 MOA but with poor ES, did those give a good group or vertical at distance? Did your scores go up or down in proportion to distance, not counting missed wind calls? Did you still see the "WTF flyers"?
I started playing with my 6ARC and a new .308 build since I shot that target and have not shot the .260 since that test. I do have 30 rounds loaded so I can check it out soon. Here are ten wounds shot at 835 that led up to that test and got me to start testing the annealing again though. Eight rounds within .5 MOA, the 9th at .7 MOA and the tenth down in the 8 ring.

Also a target shot at 300 yards in a match with annealed cases. My wind calling kicked my butt on that one.

I have another 30 rounds of that load in annealed cases I can try and shoot at 600 or 800 as soon as the swamp dries out a bit
 

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