Long Range Hunting Online Magazine Cosine and Degrees formula help please.
 Home LRH Store Forums Long Range Rifles Articles Reviews Group Hunts Shooting Classes G7 Ballistics Calculator Rules & FAQ Register Search Today's Posts Mark Forums Read

 Long Range Hunting & Shooting

# Cosine and Degrees formula help please.

#1
02-03-2009, 06:08 AM
 Silver Member Join Date: May 2008 Location: NEW ZEALAND Posts: 208
Cosine and Degrees formula help please.

Hi Guys,

Ive just watched Shawn Carlocks DVD,which I thought was very informative.

But I have a question in relation to one area that I would like answering please.

I understand the formula for the up hill/ down hill calculations with the "cosine" but what is the formula if your angle indicator is in "degrees"?

If this has all ready been trashed to death I apoligise

#2
02-03-2009, 11:49 AM
 Platinum Member Join Date: Jan 2003 Location: The rifle range, or archery range or behind the computer in Alaska Posts: 3,830
Re: Cosine and Degrees formula help please.

Bullet drop from zero - (actual drop * angle multiplier)

Actual drop is drop from a level bore not angled up for a longer zero. In other words anything past the muzzle would be a negative number.

Example:

500 yards = 40" drop from a 300 yard zero, and 88" without a zero. The shot is a 30 degree angle. The angle multiplier for 30 degrees is 0.134

40 minus (88*.134) = 28.2"

88*.134 = 11.8

40-11.8 = 28.2
__________________
__________________
Long range shooting is a process that ends with a result. Once you start to focus on the result (how bad your last shot was, how big the group is going to be, what your buck will score, what your match score is, what place you are in...) then you loose the capacity to focus on the process.
#3
02-03-2009, 12:57 PM
 Platinum Member Join Date: Jun 2001 Location: Potomac River Posts: 5,088
Re: Cosine and Degrees formula help please.

If your angle indicator is in degrees you should build yourself a little conversion chart to carry with you.

Assuming you have a windows based computer then you find in
"Programs" and then in "accessories" a "calculator". In "view" click on "scientific". Then you will have access to the trigonometry functions of which one will be cosine "cos".

Enter the angle such as 5 degrees and click Cos and it will give you the value. Do this for values up to 30 degrees every two or three degrees. Now build you a table of angles and multipliers in MS Word using small font. Print out a few copies and get the scissors and cut them out and tape one to your stock.

What you have is a lot of decimal numbers that have to be used the way Meichele said. This has to be done out int the field.

As a wise man said several times, Long range shooting is all about math.

If you get a PDA and Exbal then it does all of this stuff automatically.
__________________
The Smokin Fur Rifle Club
#4
02-03-2009, 02:23 PM
 Silver Member Join Date: May 2008 Location: NEW ZEALAND Posts: 208
Re: Cosine and Degrees formula help please.

Thanks guys.

I know the PDAs do it for you, I just like to know how the basics of getting it.
and the only indicator I can get here is in Degrees, a cosine one would be way easier to work out,even with a simple calculator in the field.

#5
02-06-2009, 06:37 PM
 Silver Member Join Date: Dec 2008 Location: Somewhere in Kansas Posts: 247
Re: Cosine and Degrees formula help please.

WOW my parents allways said i should have paid attention in math class!!!
#6
02-06-2009, 08:12 PM
 Bronze Member Join Date: Nov 2001 Location: Wyoming Posts: 92
Re: Cosine and Degrees formula help please.

FYI, the Nightforce ballistics program has an incline chart built into it. You have to have excel on your computer to use it, but it's there and will print independently of other shot information.

Coyoter
__________________
All it takes is One Good Shot!

 Bookmarks

 Thread Tools Display Modes Linear Mode

 Similar Threads for: Cosine and Degrees formula help please. Thread Thread Starter Forum Replies Last Post JAWZ Rifles, Bullets, Barrels & Ballistics 18 05-29-2015 07:51 PM Southpaw Humor 6 09-13-2010 04:52 PM jmason Reloading 10 06-10-2009 07:44 AM Southpaw Humor 1 02-18-2009 02:51 PM cjk Reloading 7 07-09-2006 08:51 AM

All times are GMT -5. The time now is 09:16 AM.