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

# 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: 3,275
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
__________________
Limits are only perceived by what has previously been achieved. Push the limits and good things will happen.

Go the distance or go home

Follow through matters. SEE THE FIRE!!!

August 2013 dall sheep: Passed one legal ram. Yes I regret it....
August 2013 Antelope: SUCCESSFULL!
October2013 Bull elk: Had to burn the tag.
It's been a GREAT year!
#3
02-03-2009, 12:57 PM
 Platinum Member Join Date: Jun 2001 Location: Potomac River Posts: 5,048
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: 245
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 Southpaw Humor 6 09-13-2010 05:52 PM JAWZ Rifles, Bullets, Barrels and Ballistics 14 11-23-2009 01:45 PM jmason Reloading 10 06-10-2009 08:44 AM Southpaw Humor 1 02-18-2009 02:51 PM cjk Reloading 7 07-09-2006 09:51 AM

 Current Poll Do you wear hearing protection while hunting? Usually do Usually do not No but I probably will in future
 Current Poll - 2 Do you have a high speed Internet connection? Yes, DSL, satellite, wireless or something else. - 89.19% No, only dialup right now. - 10.81% Total Votes: 3,052You may not vote on this poll.

All times are GMT -5. The time now is 07:18 AM.