Forums / Gun Discussion / A question of trajectory

2 years 51 weeks ago, 7:14 PM

VernDog

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Here is my question. I have seen several diagrams of bullet trajectory in which the diagram shows bullet rise after leaving the barrel. This doesn't seem logical to me, because after the bullet leaves the bore, it can't pick up any more speed and is theoreticaly slowing down. And of coarse the force of gravity starts playing it's effect. Granted, that there could be wind or atmospheric condition that makes this happen, that of coarse is not what the diagram is reffering to. If I am aiming at a givin point, say 100 yards, shouldn't the bullet shoot flat to that point, all the while physical forces pulling down on the bullet, while it overcomes these forces until they become greater than it?

2 years 51 weeks ago, 9:16 PM

soullesss

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Can you..

Can you post atleast one of the diagrams or provide a link?

2 years 51 weeks ago, 10:10 PM

soullesss

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Only reason

The only reason I'm asking to see the chart is because certain charts show the ballistic trajectory for a round fired from a zeroed hunting rifle. With this kind of chart, the barrel is angled upwards so that the bullet creates an arc.

I found the information here: http://www.chuckhawks.com/bullet_trajectory.htm

It even says "rises slightly above the level of the muzzle, but never above the axis of the barrel" .

Hope this cleared some stuff up.

2 years 51 weeks ago, 11:35 PM

runawaygun762

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Verndog

The diagrams you typically see with the arc moving upward are drawn to show the bullet path intersecting with the line of sight at a given point. You are correct in that the bullet doesn't rise that much when it leaves the muzzle, the sights are just adjusted so the muzzle is angled very slightly upward to allow the arc of the bullet to intersect with the line of sight through the sights at a known point.

A great example of this is the picture of Carlos Hathcock's M2 machine gun with the Unertl scope mounted on it that has the scope zeroed in on the coffee can he used as a 2500 yd range marker in Vietnam. You can see the barrel angled upward while the scope is basically level, showing how much angle was needed to get that bullet to that spot. It's a cool picture.

"I have always been a soldier. I have known no other life. The calling of arms, I have followed from boyhood. I have never sought another." From The Virtues of War, by Steven Pressfield.
2 years 51 weeks ago, 11:40 PM

Reaper308

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trajectory

yeah, it creates an arc. When you bzo an M16/AR at 36/300 yds, your sights will be on the POI at both distances.

"Proelium Comminus Auctoritate" "Sometimes the light at the end of the tunnel is a muzzle flash."

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