Range Report Modified BC after tipping or MV cal with a AB Kestrel?

[bdubb]

First off, I'll say that when I decided to get more involved in shooting I jumped in head first and not only started to learn shooting at increased distances but I also got a lot of toys. Which in return throws a lot more information at me than I can easily interpret at this stage in my understanding of things.

That said, I'm at a position where I have read portions of most of Litz books and stopped because some of it was just too much for me to digest at the moment. Regardless I went and got into trying out meplat trimming and pointing the Berger 140 hybrids. This weekend I attempted to see how they worked and at the same time get some experience with the AB Kestrel which I have only spent a few moments working with before this weekend. Shooting at 1000 yards, the pointed hybrids were hitting higher than the kestrel estimated which was to be expected. I made the adjustments on the scope and did the MV cal on the Kestrel and as time was running short with my buddy working the pits for me I called it good at 1000y and drove back to the pits without accepting the MV cal as I didn't know I had to at that point. So I lost some good data from the 1000y line. Shortly thereafter I was able to finish off a final 10 rounds for the day from the 600y line, which is when I noticed I lost my 1000y line MV cal data. So, I went back through the process at 600 yards. The Kestrel called for 3.35 mil at 600y and working from the target results ended up with an actual 3.25 needed which gave me an updated MV on the Kestrel.

Now is the MV cal all that is needed when adjusting for the higher BC of pointed bullets, or should the BC be adjusted where possible and then tune it further with the MV cal? I ask as I am curious about getting the proper wind information from the Kestrel. This trip to the range I wasn't able to learn as much as I needed from the wind as it was swirling a lot and I'm not at a point to judge that very well. For instance, from the 1000y line I needed no windage however on the same range from the 600y line I needed .4 mil windage. (1000y line 2-3 mph wind at 6, 600y line 10-15 wind from 5, actual impacts on target needed .4mil right windage until the winds slacked)

Back home and playing with the AB solver, the elevation I was seeing on target and my original MV with a magneto speed v2 (2784 fps) would put the BC somewhere around the .355 range which seams really high to me considering the book G7 BC is .317. Is there a happy medium with using an increased BC, and the MV cal or should I just stick to the MV cal only and use the original .317 BC to get reasonably accurate wind calls from the Kestrel?


Sorry, for all the extra BS chatter and story telling on this post for my ultimate question...

 

[bdubb]

1000y target after making some elevation adjustments from the original kestrel dope and chasing the wind. I think this might have been at 7.7mil versus the originally called for 7.9mil.

600y target with .4mil wind and 3.35mil elevation from the kestrel with original 2784 MV (orange markers). Then down 2 clicks to 3.15mil elevation and with the wind slacked off but keeping the .4 mil wind (green markers). This basically boxed in the actual elevation needed which is how I got to 3.25 mil when doing the MV cal at 600 yards.