The Down Range Forum

Member Section => Tactical Rifle & Carbine => Topic started by: twyacht on December 16, 2011, 06:35:28 PM

Title: Because You Forgot Your Trigonometry.....How Shooting At Angles Work
Post by: twyacht on December 16, 2011, 06:35:28 PM

Watch, learn, know.....Shooting uphill, shooting downhill makes no difference....

Great tutorial.



Especially, if we end up "voting from the rooftops"....

Title: Re: Because You Forgot Your Trigonometry.....How Shooting At Angles Work
Post by: tombogan03884 on December 16, 2011, 08:25:41 PM

Cool, Handy info.

Title: Re: Because You Forgot Your Trigonometry.....How Shooting At Angles Work
Post by: JC5123 on December 19, 2011, 05:26:32 PM

(http://spinstage.http.internapcdn.net/Spinstage/userdocs/skus/p_100001423_1.jpg)

These are great little tools if you find yourself shooting at angles most of the time.
Take the known range and multiply by the number (Put a decimal in front of it) and that is your true range. It saves a lot of math.

For example if your target is at 450yds and your ACI is pointing at the 87 on the dial you multiply 450yds X .87(COS) = 391.5yds

So you would adjust your sights for 390 yds. And it works the same whether you are shooting up hill or down.

Title: Re: Because You Forgot Your Trigonometry.....How Shooting At Angles Work
Post by: twyacht on December 19, 2011, 05:50:55 PM

even though I am a "flat-lander" just where can one acquire one or two of these JC?

Title: Re: Because You Forgot Your Trigonometry.....How Shooting At Angles Work
Post by: kmitch200 on December 19, 2011, 10:55:34 PM

The ones I've seen are over a $100 - like the one in the picture. (check Brownell's) Then you have to get a mount - another $60 or so. I can make a BUNCH of range cards and tape them on the stock for that amount of coin.

A laser rangefinder with an angle feature can be costly but will do the work for you. Plus you can use it for golf.  ;)

Title: Re: Because You Forgot Your Trigonometry.....How Shooting At Angles Work
Post by: Solus on December 20, 2011, 08:46:26 AM

I assume this device is an ACI...what ever that might be??  

Angle  Cosign  Indicator????


My google-fu isn't working for ACI and Brownells doesn't do any better.


Is the name of the device or a link to it forbidden knowledge?


Found it...  Angle Cosign Indicator was a correct guess.

you can see one here    http://ustacticalsupply.com/anglecosineindicator-2.aspx

Here is a link to a range finder with slope correction.     Goolged     laser range finder slope

for those with a better bank balance than math skills.

http://www.newegg.com/Product/Product.aspx?Item=9SIA04K03B3397&nm_mc=OTC-Froogle3&cm_mmc=OTC-Froogle3-_-Binoculars/Telescopes-_-BushNell-_-9SIA04K03B3397

Title: Re: Because You Forgot Your Trigonometry.....How Shooting At Angles Work
Post by: kmitch200 on December 20, 2011, 09:21:07 AM

Here's a link to Brownell's selection:

http://www.brownells.com/.aspx/cid=10062/k=/t=P/avnr%7CPrice_1%7C60%7C124.99%7CGELE=60%7C124.99/Products/Cosine-Indicators

Rangefinders from Brownell's:

http://www.sinclairintl.com/.aspx/cid=5551/Products/Rangefinders

The ones with the angle feature can also be found at most large golf shops. BassPro has one for $199.

http://www.basspro.com/Wildgame-Innovations-Laser-Rangefinder-with-Angle-Intelligence-Model-R900x/product/10206624/36851

Title: Re: Because You Forgot Your Trigonometry.....How Shooting At Angles Work
Post by: fightingquaker13 on December 22, 2011, 11:47:28 PM

Why do I suddenly get a flashback  to the guys from "Revenge of the Nerds" kicking Vassily's ass in "Enemy at the Gates II". ;D
FQ13