Ballistics Chart Help

[Etxbuckman]

Can someone help explain something to me: I was under the impression that, if I have my rifle zeroed at 100 yards, it would be 3.5” low at 200, meaning I would have to aim 3.5” high to hit my spot at 200.

But a friend is telling me I’m reading this wrong and it’s actually 1.8” low.

How am I supposed to read this stupid thing??

[sboudreaux]

You are correct Sir.

[Etxbuckman]

You are correct Sir.

So if I sight in 3.5” high at 100 yards that puts me dead-on at 200?

[Jonathan]

If you sight in 1.8" high at 100 you will be on at 200.

[sboudreaux]

He's correct ^

[huntandfishguy6]

The answers given are correct. It will be 7" low at 300 if I remember correctly.

[Plain Lucky]

I am of the opinion that you are both correct, and both wrong, based on your chart's incorrect data.

One column shows a 3.5" drop from 100 to 200, yet the other shows a 1.8" drop from 100 to 200.

And then it shows a drop of 9.3" from 200 - 300, yet the other column shows a drop of 7.5" from 200-300.

Curious on the source of your chart?

[Plain Lucky]

For what it's worth, Hornaday factory 139gr SST indicates 1.5" of drop from 100 to 200, and 7.5" of drop from 200 to 300. Their factory ammo tends to be loaded a little hotter than others but I trust their chart as it pertains to their ammo.

[db@100]

One column shows zero at 100 yds. The other column shows zero at 200 yds.

[muzzlebrake]

Find a Ballistics curve graph rather than a nomograph might help you understand bullet drop better. https://shooterscalculator.com/balli...php?t=7be14204

[scott123456789]

You are missing a key issue with aiming. 1” high at 100 yards is 2” high at 200 yards.

with a 100 yard zero you will be 3.5” low at 200 but you only have to account for half of that since you are talking about 200 yards. So you would site at 1.75” high or the 1.8 they list on the chart.

[Plain Lucky]

You are missing a key issue with aiming. 1” high at 100 yards is 2” high at 200 yards.

with a 100 yard zero you will be 3.5” low at 200 but you only have to account for half of that since you are talking about 200 yards. So you would site at 1.75” high or the 1.8 they list on the chart.

Using the 100 yard zero column: 1" high at 100 is 2.5" low at 200, not 2" high at 200

Sorry brother but you are also incorrect about "accounting for half" from 100 to 200. Every caliber has different ballistics and you have to go by the specific chart that is created for the applicable caliber and each particular load. In this particular case, his 7mm-08 shooting a 140gr ballistic tip using the load specified, according to the 100 yard zero chart, the bullet drops 3.5" from 100 to 200. He can:

- sight in 3.5" high at 100 and be zero at 200
- sight in at 2.5" high at 100 and be 1" low at 200
- sight 1.5" high at 100 and be 2" low at 200
- sight in 1/2" high at 100 and be 3" low at 200, etc.....

The chart in the OP's initial post is wrong. I can't answer which, if either, of the 100 or 200 yard zero columns is correct but the math has to jive between the two columns, and it doesn't.

[scott123456789]

Plain Lucky you are getting caught up in bullet paths but ignoring how MOA works. 1 moa is approximately 1” at 100 yards but that same angle is 2” at 200 yards. So my comment about half is critical. If you move your cross hairs one inch at 100 yards, your cross hairs move 2” at 200 yards.


the two charts posted are both correct.

[scott123456789]

So if I sight in 3.5” high at 100 yards that puts me dead-on at 200?

If you sight in 3.5” high at 100 you will be sighting in 7” high at 200 yards. However you only drop 3.5” so you will still be 3.5” high at 200 yards.

the following comments about 1.8” high is where you want to be. That will be 5.4” high at 300 yards but your bullet is dropped nearly 13 which is why the chart on the right says you are 7.5” low at 300z

[TacticalCowboy]

Just zero it at 200. Out to 250, you don’t really need to worry about drop or anything else. Just put the crosshair on the deer and pull the trigger.