I don’t claim to be an expert but I will make a couple recommendations. I think you are looking at a ladder that is difficult to interpret. If you have the ability to test at 500 yards the target will likely be easier to interpret since you are looking for a point where multiple charges print at or near the same elevation. Even at 500, single shot ladders can be tricky to interpret. I have had some success doing so but you do run the risk of one errant shot pointing you in the wrong direction. As an example, here is a 500 yard 6BR Improved ladder I shot a week ago.
View attachment 1103578
I guessed my node I wanted to pursue was 30.5 but now I think I got lucky. 30.4, 30.5 and 30.6 showed about half an inch of vertical so I picked the center and shot a 4.5” group at 1K but I’m glad I didn’t stop there. I also liked 30.7, 30.8 but the second ladder test, this time at 1K told a different story.
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Please note there are two shots for each charge. I actually started with three but a surprise wind shift forced me to finish the test with 2 shots per charge. On the first ladder, 30.4 printed above 30.6 and below 30.5. Not so on this target, and I put more faith in this one.
Now 30.5 and 30.6 still still to overlap but 30.4 prints low. Next group testing will be at 30.55.
30.7 and 30.8 printed together at 500 but at 1K the second 30.8 shot which you can’t see in the photo, printed about 6” higher than the first. Had I chased say 30.75 I would have been wasting time.
The best advice I can give would be shoot ladders at the longest distance possible, if not the range you intend to compete or shoot at. Wait for the best conditions you can. Shooting multiple shots, especially as the range gets longer, should improve your confidence level in the results.
Dave.