I haven't seen you explain what your ladder test is for (so I might be wide of the mark so to speak) but as I understand, ladder tests are only effective beyond 200 yards, inside that the vertical separation of rounds at different velocities or vibration nodes hasn't happened yet . . as I mentioned I shoot mine at about 320 metres.
There is a method for achieving a similar result at 100, its called "Optimal charge weight" or OCW, but I have never really been able to get my head around it.
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