well you have a couple of options
1. Use a online ballistic calculator to figure your drop numbers then go shoot to verify and fine tune your numbers.
2. post your load info here for someone to figure your drops for you and the go shoot to verify and fine tune your numbers. Need caliber bullet weight type velocity to figure it
3. Go out and shoot it working up in moa unitll you get on target at each range(this ooption will require lots of shooting while this is alot of fun its allso expsensive)
Most calculators will get you within a click or two
retiredcpo
