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Hi, I'm playing around with Bryan Litz's Applied Ballistics for boing and have an output I'm struggling to understand.

Using a .308 and a 178gr AMAX with a 100-yard zero and 10 mph wind from 3 o'clock produces an output table that reads as below for drop/path:

0 yards: 0.0
50 yards: U0.6 MOA
100 yards: D0.4 MOA
150 yards: U0.2 MOA

I would normally expect to see 0.0 of adjustment required at 100-yards for elevation with a 100 yard zero. Why is this giving me up then down, then up between 50-150 yards ?

To compound my confusion, if I take wind out of the equation by setting that item to 0mph it ends up giving me 0.0 elevation at 100-yards. I would expect to see 0.0 drop irrespective of wind at 100-yards but the larger wind call I make, the more drop is required according to the output.

I emailed Bryan but didn't get a reply and was hoping somone could explain what's going on here ?

Thx

Ive just added this bullet in to my AB and come out with a 0 at 100yds - have you got scope height and zero height set?

Adding wind makes no difference on my version.

I have zero elevation correction and zero height offset. I have 2.25 sight height but even if I change that to 10 inches it doesn't change my drop at 100-yards. Weird that wind seems to impact drop and that is with any bullet/load I select.

To replicate your figures I neet to put a 125yd zero - ive guessed your m/v at 2600

2700 but I get similar results with other bullets at diff velocities. Weird.

Disable spin drift and corriolis effect. This will effect your poi in AB depending on entered barrel twist and direction.

Once established that is the cause you can re enable and all is right ;-)

Wind from the right will lift the bullet slightly in flight, and lowers from the left. That's your reason.

Swamp Donkey wrote:Wind from the right will lift the bullet slightly in flight, and lowers from the left. That's your reason.

Only in rifles with a right hand twist

Spin drift and coriolis disabled. Do you too get elevation adjustment based on wind ? Oddly, it is giving me less elevation adjustment assuming a 500 yrd zero vs a 100 yrd zero for a 10 mph wind. If it were the supposed Magnus effect would it not be greater impact at distance ? Never seen a ballistic app adjust for this before. Thx