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lionhunter

Down hill shot question

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Coach,

 

You're absolutly right. We TOTALLY hi-jacked this thread. My apologies.

 

Lionhunter, I am sorry we turned your thread into an abomination.

 

Maybe in the near future I will send an article to Amanda and see if she wants to post it about the practical application of compensating for up and downhill shooting WITHOUT the vacume.

 

rclouse79: Happy hunting. If I were to offer any advice, please dont take any shots up or down hill. :lol: :lol: :ph34r:

  • Haha 1

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i think that everyone is over thinking this the second post had it right you aim and put the dope in the scope for the actual horizontal distance whether you are shooting up or down 308nut you are more than right with atmospheric conditions and external data affecting the trajectory

 

but to break it down Barny style there is a myth busters show that shows them dropping a bullet and it takes X amount of time to drop 40 inches and they fire the bullet and it takes the same amount of time to drop 40 inches... long story short the higher the velocity the longer the distance it takes to drop the 40 inches based on the earths gravity

 

they teach this at the school of infantry in the marines that up or down that you hold for the horizontal distance between you and the target because gravity is only affecting trajectory latterly between the two points

 

some rangefinders have the angle in degrees calculated into a ballistic range for you and show the degrees (i forgot what brand) but they are out there

 

and with coach he is right it doesn't take a phd.

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man im glad i hunt manly archery hahaha just hold a little low as i was always told. ha my only coues was at 75 yards flat and every deer i have had a chance at was under 200 yards. not saying you guys are wrong or bad or anyhting like that but at over 700 yards to me it becomes killing and not hunting just my two cents.

 

 

for lion hunter id say same as archery just hold a little low and you should be good two 500 or so. just my none long range pda shoot thinking.

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One thing I would like to reinforce is that illustration found at that link shows two different illustrations. One is of one yardage versus another yardage of 400 yards and 280 yards (line of sight versus line of sight * cosine) and the chart is based on actual bullet drop * cosine. It is the actual bullet drop * cosine that is conciderably more accurate than yardage * cosine. Actual drop * cosine will keep you out of trouble most of the time where shooting for the line of sight yardage * cosine will cause misses. Tow very similar methods yet two very different results.

 

The link below will back up what I am preaching here and was written by someone who actually has credentials. Please note, he uses similar illustations as found at the link in the previous post but he also explains the accuracy differences between these two different techniques.

 

On that note I hate the many angular illustrations as they lead shooters to think that taking yardage * cosine is an accurate solution when it is not. It does a great job of showing the principals of why it happens but does a very poor job of showing accurate compensation. With added variables like scope height and bore angle, air density etc....it isnt as simple as line of sight yardage * cosine which is very contrary to popular belief.

 

A small excerpt taken from the article below:

"1) You spot your target. 2) Range / obtain the distance to your target by either utilizing a laser range finder or a ranging reticle. 3) Aim at your target and then look off to the side of your rifle at the Angle Cosine Indicator and obtain the indicated Cosine number. 4) Multiply the cosine number to the distance to your target, which will give you a corrected for gravity distance.

 

For example, 500 yards X .7 (45 degrees) = 350 yards. Now, look at your data card to obtain your hold for the 350 yard target distance, and adjust your turrets as specified. However, this is the least accurate method."

 

http://www.longrangehunting.com/articles/angle-shooting.php

 

Aside from the link above, other 'credible' references are the Sierra Reloading Manual (4th Edition) and Understanding Firearm Ballsitics by Robert Rinker.

 

Not trying to me a jerk or a know it all, seriously just trying to help other coues whitetail fans succeed.

 

M

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What no mention of bore scope (height) offset adjustment on trajectory? :lol:

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Just keep shooting until you hit him, not much time to get calculator and protractors and barometric pressure readings, just carry lots of bullets.But most importantly trust your instincts.

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Having given this shooting at an angle some thought over the years I have developed a strategy. I did get a range finder that corrects for angle and found I did not use it enough to keep all the different mode & displays straight. So I left the laser ranger on the straight line of sight distance mode. Did this because in the heat of battle what I really needed was 250 vs 300 vs 350 vs 400 (past 400 needed more thinking time than just simple estimation). With a cross hair that has some kind of marks, hold a little under when shooting 20 degrees +/- bellow level. I figure when your angle is a 1/3rd to 1/2 bellow level Hold like its almost 40 yards closer. Have only used strategy twice at 300 yards, worked out well.

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Holy cow what a ballgame. The deer is miles away by now. So how many actually took the shot @ the rock next to where the deer was, to see if all miscalculations actually worked in the real world?

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Most rangefinders can compensate for angle but hers a cheat sheet.

5-10 degree slope = 98% of slope distance
15-20 degree slope = 95% of slope distance
25-30 degree slope = 90% of slope distance
35-40 degree slope = 80% of slope distance
45 degree slope = 70% of slope distance

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