can someone explain……????????
why, when you sight in on level ground your poi changes when you are shooting up/downhill???? do you aim high or low when shooting down/uphill???
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It doesn’t, BUT, there will be less arc. What happens if you shoot exactly straight up? The projectile will ascend to it’s zenith, (With out arc). It will then Because of gravity, (which has been slowing it down all along) make it come back down and hit you in the head! 😉 😆
Actually , if exactly straight up, it would have hit the muzzle of your still raised gun, but there was a slight wind. So now your fucked! 🙄 😆 😆 😆 😉
Go out side wigh a garden hose and shoot it from level to stright up. You will quickly see what we are trying to teach you. If that doesn’t do it, try it pissing in stead of a garden hose. You’ll get it then I’ll bet! In more ways than one. 😈
Can someone explain why gravity hasa reduced effect when shooting upwards? I get the downwards part.
Gravity consist’s of a vertical component. In the extremes – items travelling vertically can only be slowed or accellerated by gravity but their course remains the same (until an upwards travelling object is slowed and then accellerated back down…. but that can be ignored due to the fact were not talking about pellets stopping and going back where they came from) and items travelling perpendicular (horizontal) to gravity can have their course deviated which is what causes the change in POI….
Therefore items travelling at an angle will have their course deviated… but because part of their travel is in the vertical component and slightly less is in the horizontal component their course isnt affected as much (the object is slowed… which does lead to gravity acting on it for longer but it can be ignored in this for simplicity sake).
So…. There IS a negligiable (in our case) difference between shooting uphill and shooting downhill and that is that the uphill shot will be deaccellerated by gravity, which means that it takes longer to hit the target so gravity has longer to act on it – but that difference is MUCH less than the difference caused by the incline postive or negative and both will hit in a similar place at airgun ranges.
Or.. you could just read the link that gipetto has posted twice now that is likely much more accurate than anything I’m reciting from 10 year old engineering class.
Did you post a link? 😆
It seemed to make sense that it would drop more when shot higher up for some reason.
Can someone explain why gravity hasa reduced effect when shooting upwards? I get the downwards part.
Lets say you are shooting at a rabbit (38) yards away down in the creek bed and you are 15 feet higher than bugs.You would shoot the wabbit at say (32) yards because of arc?
Something like that yes.
Rule of thumb I use is to estimate or rangefind the distance in a straight line to target and use that. I dont rangefind up a tree – I’ll rangefind to the base of the tree at my eye level.
Yes because the arc would be less severe
so let me try to understand .
Lets say you are shooting at a rabbit (38) yards away down in the creek bed and you are 15 feet higher than bugs.You would shoot the wabbit at say (32) yards because of arc?
I shooting him for (38)yards being gun bow or bowling ball
You aim as if the target is closer wether its shooting up or down. Your theory is incorrect – gravity has a reduced effect in both cases.
Was I being too subtle? My bad.
i have to disagree with the gravity thing, We were told 30 yards is 30 yards,looking up hill or looking down hill will only throw your mind off of true yardage + – but 30 yards is 30 yards.And a arrow going 300 fps.And a pellet going 800-1200 fps being affected by gravity,it only appears that way.
but its a great debate to find out, I could be wrong
The higher or lower the arrow or barrel is aimed, the less arc you will have in the trajectory… Think about how much arc there is if you shoot straight up or straight down… Gravity is still in play but there is no arc…..
but if i shot a 30 yard target straight up at 300-or 1200 fPS or a target at 30 yards straight down (Newtons Law) its still 30 yards ,Arc and gravity or the formula of flight is when lift + thrust is grater than load + drag
Doesn’t matter how fast you shoot something straight up, it will not have
an arc……Pellets, bullets, and arrows do not lift or take flight…. They are
pointed upwards from the start.. In relation to the bore, they are all falling
the second they are shot…..
This illustration explains it simply.
http://www.arld1.com/targetplottrajectory3.html
OK… Your POI @ 30yds level will be lower than your POI @ 30yds if you are
raising or lowering the bore to a 45deg angle or anything higher or lower
than level….. Changing the POA angle changes the arc of the trajectory
therefore you have to adjust your POA so that the POI will hit the target….
If I use 1 mildot high to hit a target at 30yds level then I would have to use
more mildots (maybe 1.5) to hit a target up in a tree at the same distance….
i have to disagree with the gravity thing, We were told 30 yards is 30 yards,looking up hill or looking down hill will only throw your mind off of true yardage + – but 30 yards is 30 yards.And a arrow going 300 fps.And a pellet going 800-1200 fps being affected by gravity,it only appears that way.
but its a great debate to find out, I could be wrong
The higher or lower the arrow or barrel is aimed, the less arc you will have in the trajectory… Think about how much arc there is if you shoot straight up or straight down… Gravity is still in play but there is no arc…..
but if i shot a 30 yard target straight up at 300-or 1200 fPS or a target at 30 yards straight down (Newtons Law) its still 30 yards ,Arc and gravity or the formula of flight is when lift + thrust is grater than load + drag
aim at the base of the tree say 30 yards away as you aim higher the distance shooting is farther
i use a range finder bowhunting that has a built in angle meter thing
it detects the angle shooting and gives the true distance to the target
i have to disagree with the gravity thing, We were told 30 yards is 30 yards,looking up hill or looking down hill will only throw your mind off of true yardage + – but 30 yards is 30 yards.And a arrow going 300 fps.And a pellet going 800-1200 fps being affected by gravity,it only appears that way.
but its a great debate to find out, I could be wrong
The higher or lower the arrow or barrel is aimed, the less arc you will have in the trajectory… Think about how much arc there is if you shoot straight up or straight down… Gravity is still in play but there is no arc…..
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Can someone explain why gravity hasa reduced effect when shooting upwards? I get the downwards part.
Gravity and wind affect the shot in the same manner….If the wind is blowing
left to right, you have to aim left of the target. Your shot will move to the
right more if the wind is blowing across at a 90deg angle. . If you shoot
straight into the wind the shot will not move left or right, therefore there
would be no windage correction…. The force of gravity is Straight down just
as the wind would be straight across… The more you shoot directly into or
away from the force, the less affect the force has on the projectile.