Fieldcraft How does one calculate LOS angle?

[toyfreak]

Savage 10fcp .308 Hornady Match 168 bthp


I was out shooting at a new range this past weekend and
I came into a situation that i wasn't sure how to handle.

We were shooting at a 12in steel plate at 770 yards, ballistic FTE says -69 mil but to hit I had to dial in -59. I had noticed before we started shooting that we were much higher than the target but didn't realize how much it mattered until I started hitting. Missed high with the first 2 then hit the next 3.

If i were to guess i would say that we were aprox. 100' higher than the target, but just a guess.

So my question is what is the proper way to figure LOS angle in this situation?
thanks

 

[Lindy]

Re: How does one calculate LOS angle?

Well, first you have to measure the angle to the target. There are a number of methods of doing that. You can use a Mildot Master, a Slope Doper, an Angle Cosine Indicator, or some other method.

Then you have to figure out how much that affects your dope.

The Improved Rifleman's Rule is to multiply your dope for the actual distance to the target by the cosine of the angle to the target.

See:

Angled Fire Explained

Or just go into Ballistic FTE. Turn on LOS Angle in the HUD, and point it at the target, keeping the device perpendicular to the line of sight to the target. It will then correct your dope.

 

[KNIGHT11B4]

Re: How does one calculate LOS angle?

If you were 100 feet above the target then your flat ground distance was about 725. But don't quote me that's was 'head math' and its early.

As Lindy said get an ACI or use one of the other methods to be sure.

 

[toyfreak]

Re: How does one calculate LOS angle?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Lindy</div><div class="ubbcode-body">Well, first you have to measure the angle to the target. There are a number of methods of doing that. You can use a Mildot Master, a Slope Doper, an Angle Cosine Indicator, or some other method.

Then you have to figure out how much that affects your dope.

The Improved Rifleman's Rule is to multiply your dope for the actual distance to the target by the cosine of the angle to the target.

See:

Angled Fire Explained

<span style="color: #3333FF">thank you for the linky</span>

Or just go into Ballistic FTE. Turn on LOS Angle in the HUD, and point it at the target, keeping the device perpendicular to the line of sight to the target. It will then correct your dope.

<span style="color: #3333FF">I tried this but i guess i wasn't sure of the proper technique for getting an accurate reading.</span>

</div></div>

 

[toyfreak]

Re: How does one calculate LOS angle?

when i hit i then put the dope in FTE and it said 700yrds

 

[Lindy]

Re: How does one calculate LOS angle?

A corrected distance of 700 yards when the actual distance was 775 yards would indicate that the angle was <span style="font-style: italic">around</span> 24 degrees.

 

[Guest]

Re: How does one calculate LOS angle?

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: toyfreak</div><div class="ubbcode-body">Savage 10fcp .308 Hornady Match 168 bthp


I was out shooting at a new range this past weekend and
I came into a situation that i wasn't sure how to handle.

We were shooting at a 12in steel plate at 770 yards, ballistic FTE says -69 mil but to hit I had to dial in -59. I had noticed before we started shooting that we were much higher than the target but didn't realize how much it mattered until I started hitting. Missed high with the first 2 then hit the next 3.

If i were to guess i would say that we were aprox. 100' higher than the target, but just a guess.

So my question is what is the proper way to figure LOS angle in this situation?
thanks </div></div>

As already said you can use angle then re-math it.

Or you can mod a reciever mounted angle gauge, that reads in the amount of percentage difference.
Wind is still real range, not corrected.