A Problem For The Ballistically Inclined...

[SA Friday]

At 25 yds, your paper impact in comparison to your scope zero will essentially be the same as the distance from the center bore axis of your barrel to the center of your scope. The bullet is travelling straight from the muzzle to the paper, so your impact in comparison to where aimed should be about 2 to 2 1/2 inches low. This is a real rough estimate as the bullet from a 308 will still be travelling at an upward arc at 100 yds and depending on the set-up won't reach it's unaltered vertices till somewhere in the range of 200 to 250 yds.

[jmg8550]

A 25 yard sight in for a .308 will get you very close at 200 yards. Aim for 2-3 inches high.

[wilsonpenfam]

the ballistics calculator says 20yds 0.8in low, 40yds 0.3in low

[OgenRwot]

That's only if you know what he's getting for velocity with his loads at his altitude with his bbl at his temp etc etc.

Basically, OP, you can only get ballpark at the very best.

[mikeh1911]

The answer is 1.4 inches low from http://www.jbmballistics.com/ with the following data.
150 grain 308 bullet traveling at 2700 FPS with a bc of .4 and a zero of 100 yards. A 2.5 sight above bore, temperature of 70 degrees, humity of 30 percent, preasure of 25.00hg, altitude of 5500 ft. At 200 yards you will be 2.8 inches low or -1.8 MOA

This is still going to be a ball park figure that should get you on paper at 200 but need to shoot 100 and 200 yards to confirm.

Hope this helps.

Mike

[SA Friday]

The answer is 1.4 inches low from http://www.jbmballistics.com/ with the following data.
150 grain 308 bullet traveling at 2700 FPS with a bc of .4 and a zero of 100 yards. A 2.5 sight above bore, temperature of 70 degrees, humity of 30 percent, preasure of 25.00hg, altitude of 5500 ft. At 200 yards you will be 2.8 inches low or -1.8 MOA

This is still going to be a ball park figure that should get you on paper at 200 but need to shoot 100 and 200 yards to confirm.

Hope this helps.

Mike

My guesstimate was a little low now that I think about it. This sounds spot on. An inch or two isn't going to throw you off paper though at 100 yds.

For everyone saying to sight in high: Epic Failure in the understandings of ballistics. Feel shame