Re: Newbie ammo question
Bravo for figuring that out. It shows dedication and ingenuity.
Before you trust the computations completely, I'd suggest confirming the results at some of the distances.
The box ballistic chart makes general assumptions that influence the data's validity. Confirmation will determine whether any adjustments or compensations might need doing for your particular rifle. Quite often some variance between comps and practical experience will appear.
You might also want to consider that factory loads may or may not remain supersonic out to 1000yd. Transsonic and subsonic portions of a trajectory can behave out of character compared to the supersonic portion.
Just keep your eyes and mind open, and you'll do fine.
Greg