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point of aim vs point of impact


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Hi, just wanted to see if anyone is also experiencing the same thing as me and if I might be doing something wrong, would be great to know some techniques.


About 20 yards away, IPSC plate. shooting at an angle downwards. In short the shooter is high and the targets are low. I aim dead center on the steel and I miss because the impact is way high on the steel. I need to do a 6 oclock hold + about an inch lower on the plate  - then I hit the plate. Is this because of the angle of the shot. Is this normal?


I tried to zero the gun today, its a STI Edge 40, on a plate rack and to my surprise, at about 12-15 yards, it is dead center.


While at this topic, for steel plates out to 30-40 yards, which unfortunately I could not practice at our range due to the size limitation,  would one expect to remain dead center or does the bullet actually go higher?

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The hill is your issue.


Remember that just like a man throwing a ball, it leaves at an upward trajectory and then falls in a graceful curve until it intersects with your target... placing the target well above or below the origin point affects where along that ballistic arc the bullet impacts the target.


To put it simply:


If you are shooting noticeably uphill OR downwhill, you must aim low in both cases.


Anyone who’s missed a deer on a mountainside is familiar with this phenomenon. It sounds wrong, but do some googling. It’s true.


Expect the bullets to always hit high if you’re shooting on any kind of incline/decline.


And do all of your sighting-in on flat ground:


If you’re sighted in at 12-15 yd then your rounds should hit lower at 20-25 on flat ground. However it’ll be a miniscule difference, perhops 0.5” or so. Unless you’re exceptionally accurate you might not even notice it.


I sight in at 15yd then verify it with a 10rd group at 25, personally.


Edited by MemphisMechanic
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Just for the sake of clarification, the bullet starts dropping as soon as it leaves your barrel; however, the bullet does “rise” initially in reference to the line of sight.  This is why if you sight an .223 in at 25 yards, it will generally also be on at 100 yards.  The closer the sights are to the center bore axis, the less “rise” you will see.   In pistols, the velocity of the bullet will make a difference but generally only when you are getting out to at least 35+ yards.  This link compares 9mm vs .40.


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12 hours ago, jimbullet said:

 30-40 yards,  does the bullet  go higher?


Really depends on how you've sighted your gun in and the velocity of the bullet.


You really have to try it, and see where the bullet goes at 40 yards - highly

recommend that no matter how you sight the gun in.


I usually sight my gun in at 50 yards, and check where it hits at 10 and 25 yards   :) 

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9 hours ago, sdm702 said:

that must be a pretty extreme angle to be missing at 20yrds. If you are say shooting at a 45 deg angle at a range of 20 yrds your  angle corrected range at that angle would be 14.14yrds.


Right. 20y x cosine 45* = 14.14y the horizontal distance travelled by the bullet and which the drop of bullet due to gravity is derived. Not the sloped distance. If gun is zeroed at 20y that means horizontal distance of 20y. If its the first zero and it was aimed at 20y at a steep angle the horizontal distance is lesser and POI should be below POA. Because at this hor. dist. the bullet is still below the line of POA. It will hit POA at equivalent 20y horizontal. 

Edited by BoyGlock
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So, using the example above, a 10°  change in elevation of the plates would equal about a 41" height difference in the plates.


20y*cos10°=19.7 yds.


So you are saying that 10" in distance changes to POI enough to miss the plate?


Or is "jimbullet" standing on top of a hill shooting down on the plates?

Edited by TDA
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my trigonometry above needs the actual trajectory of the bullet for it to be useful. Its more of an aid in understanding that bullet drops in trajectory is vertical and a factor of horizontal distance. In rifle round trajectory it may be more obvious. In pistol its less obvious unless it is shooting at a very steep angle and at considerable distance for a pistol round to have a measurable drop (say 50 or more yards?)

Say at 150 horizontal yards my rifle round is 6” vertically high or below of POA, at 35* inclination, the sloped distance will be 150y / cosine 35* = 183.12y to have the same 6” variation from POA. 

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  • 1 year later...
10 hours ago, Blackstone45 said:

It helps if you have a question.


My 9mm is sighted in for 25m, and at 50m, I find I have to hold just under the black on a standard 50m bullseye target

What is that distance? About 2"? Or it is more than expected


I meant about the plate being low. Any explaination with examples? What formula should I check for? 

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3 hours ago, xdf3 said:

What is that distance? About 2"? Or it is more than expected


I meant about the plate being low. Any explaination with examples? What formula should I check for? 


basically, when you shoot on an incline, you have to work out the actual horizontal distance between you and your target, and hold for that.

Let's say you're shooting at a target 1000 metres away at a 20 degree incline. With a bit of trigonometry, you can work out that your horizontal distance to your target is 940 metres. 


So instead of holding for 1000 metres, you would hold for 940 metres. 

If you did hold for 1000 metres, your shot would go high as expected.

Edited by Blackstone45
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