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Rogerflat · Silver Status Member

What is it with airguns and angles and trajectories. Shooting slightly downward (from a one story window to the ground) my gun is 1 inch low at 10 yards. But then I was shooting upwards into a tree at 18 yards and it was 3 inches high! I find myself having to plot out all of these places in my yard and remembering where my rifle shoots at those angles and distances, but it is a pain in the asss. I would think that at such short distances the rifle could propel the pellet to where the center of the crosshairs are without such extreme variances in POI.

Target shooters have it easy because they sit on a bench, shoot flat, and only worry about distance.

23ib0d0n · Moderator

There are only 2 distances a trajectory can intersect the sight line. Put a laser parallel to the barrel then, go shoot at targets at different distances.

Trajectory is only one thing, 32fps/sec toward gravitational pull. Time in flight determines how much distance drop, as rate of fall is gravitational constant.

Rogerflat · Silver Status Member

Yeah, I'm just amazed that the pellet not only crosses the sight line within a 10 yard stretch, but moves 4 inches!

I always thought that at like 10 yards and 30 yards the POI was dead on. At 20 yards it is an inch high, at 5 yards and 40 yards its an inch low. This obviously depends on what distance you sight in at, but it looks something like that, with the parabola intersecting the line of sight twice.

DelfinJager · New Member

The shift of point of impact comes from gravity Vs. vertical velocity. When shooting level the pellet has very little if any vertical velocity. Increase your upward angle and now gravity is fighting the velocity of the pellet which is much higher than the slight upward velocity from shifting the gun a few MOA higher.

2RCHA · Veteran Member

What distance is your scope set-up at?, I set-up my scope for 20yd's, at least I know the line of sight will cross twice, at 20yds, and at 40yds,,For distances in between, Is where my Mil-Dot comes into play,,set up targets at 10yd intervals, and then see where each shot goes at 10,20,30,40,50 yds on the Mil-Dot,Work's pretty good for me,,but that's using the same round you set-up the scope with,, if you decide to change ammo, you'll have to do this with each new pellet you use, unless you have a gun thats not pellet fussy. Cheer's, Andy.