Forums
New posts
Search forums
What's new
Articles
Latest reviews
Author list
Classifieds
Log in
Register
What's new
Search
Search
Search titles and first posts only
Search titles only
By:
New posts
Search forums
Menu
Log in
Register
Install the app
Install
Forums
Hunting
Long Range Hunting & Shooting
Shooting up hill/ Shooting down hill?
JavaScript is disabled. For a better experience, please enable JavaScript in your browser before proceeding.
You are using an out of date browser. It may not display this or other websites correctly.
You should upgrade or use an
alternative browser
.
Reply to thread
Message
<blockquote data-quote="Michael Eichele" data-source="post: 500248" data-attributes="member: 1007"><p>What most shooters dont understand is why we cannot just take the bullet drop and multiply it by the cosine of the angle.</p><p></p><p>The reason you cannot do this and expect great accuracy is because there are OTHER angles at play and not just ground youre shooting on. It is for this reason that you have to take the 'bore line' drop and multiply that by the cosine of the angle. This value gets deducted from your 'corrected' bullet drop (drop from zero).</p><p></p><p>Think about this:</p><p></p><p>You're rifle is zeroed at 300 yards. You are firing on perfectly level ground. Is your rifle barrel level? No matter how fast or flat your rifle is the only way to hit your 300 yard target is to tilt the barrel up. Your bullet then rises higher than your crosshairs when aimed at your target. If you agree please read below.</p><p></p><p>Now think about this:</p><p></p><p>You take that same rifle and fire it at a target 1000 yards away that is 90 degrees straight up. Can you multiply the range by the cosine and expect to hit your target? No. The cosine of 90 degrees is 0. You would be trying to shoot for 0 yards. How do you bring your scope in alignment to shoot 0 yards? If you raised the scope above the rifle so high that it could look down at the muzzle for a 0 yard shot, how would that benefit you at 1000 yards? IT WOULDNT. Even if you took and multiplied 1000 yards by the sine of 90 degrees which is 1.0, could you zero your scope and just aim for 1000 yards? No. </p><p></p><p>If you zero your rifle for 1000 yards on a level surface and then switch back to that 1000 yard target straight above you, why will it hit high, or in this case high in relation to the target but really behind you? This is because the rifle barrel is tilted 'up' remember? In this case, the barrel is NOT 90 degrees up. It is over 90 degrees. As you fire, the bullet crosses your line of sight and just keeps on going behind you. Remember gravity? This is how gravity affects your bullets in this context. That said, the only way to hit that 1000 yard target 90 degrees up is to get the forces of gravity to act soley on the front of the bullet. The only way to do that is to adjust our sights in a way that will move our barrel to 90 degrees straight up.</p><p></p><p>The above is the most extreme example but it shows why multiplying the range by cosine does not work. However, if you apply Sierra's formulas, you will DRILL that target.</p><p></p><p>So yes, there are 3 methods. 2 are useless for extreme angles and ranges, the other is spot on. Can multiplying the cosine by the bullet drop work in some cases? Absolutely. In most cases in fact. When you start hunting goats, sheep and other rugged mountain critters though, you had better use the right method.</p><p></p><p>M</p></blockquote><p></p>
[QUOTE="Michael Eichele, post: 500248, member: 1007"] What most shooters dont understand is why we cannot just take the bullet drop and multiply it by the cosine of the angle. The reason you cannot do this and expect great accuracy is because there are OTHER angles at play and not just ground youre shooting on. It is for this reason that you have to take the 'bore line' drop and multiply that by the cosine of the angle. This value gets deducted from your 'corrected' bullet drop (drop from zero). Think about this: You're rifle is zeroed at 300 yards. You are firing on perfectly level ground. Is your rifle barrel level? No matter how fast or flat your rifle is the only way to hit your 300 yard target is to tilt the barrel up. Your bullet then rises higher than your crosshairs when aimed at your target. If you agree please read below. Now think about this: You take that same rifle and fire it at a target 1000 yards away that is 90 degrees straight up. Can you multiply the range by the cosine and expect to hit your target? No. The cosine of 90 degrees is 0. You would be trying to shoot for 0 yards. How do you bring your scope in alignment to shoot 0 yards? If you raised the scope above the rifle so high that it could look down at the muzzle for a 0 yard shot, how would that benefit you at 1000 yards? IT WOULDNT. Even if you took and multiplied 1000 yards by the sine of 90 degrees which is 1.0, could you zero your scope and just aim for 1000 yards? No. If you zero your rifle for 1000 yards on a level surface and then switch back to that 1000 yard target straight above you, why will it hit high, or in this case high in relation to the target but really behind you? This is because the rifle barrel is tilted 'up' remember? In this case, the barrel is NOT 90 degrees up. It is over 90 degrees. As you fire, the bullet crosses your line of sight and just keeps on going behind you. Remember gravity? This is how gravity affects your bullets in this context. That said, the only way to hit that 1000 yard target 90 degrees up is to get the forces of gravity to act soley on the front of the bullet. The only way to do that is to adjust our sights in a way that will move our barrel to 90 degrees straight up. The above is the most extreme example but it shows why multiplying the range by cosine does not work. However, if you apply Sierra's formulas, you will DRILL that target. So yes, there are 3 methods. 2 are useless for extreme angles and ranges, the other is spot on. Can multiplying the cosine by the bullet drop work in some cases? Absolutely. In most cases in fact. When you start hunting goats, sheep and other rugged mountain critters though, you had better use the right method. M [/QUOTE]
Insert quotes…
Verification
Post reply
Forums
Hunting
Long Range Hunting & Shooting
Shooting up hill/ Shooting down hill?
Top