A spotter error I noticed.

41 414gates 2 years ago

I've seen a spotter calling shots "net onder deur" / "just under " on the 2 mile target.

The target is off the ground. From the shooting position, the ground behind the target is visible under the target.

In the diagram, the curve is the bullet path, the doted line is line of sight, and the red is the target.

The bullet impact appears on the ground close behind the target, between the target legs.

If the bullet was a laser, then yes, it can be said that it passed under the target.

The bullet is on an arc, the highest point of which is tens of meters above the ground,

It drops behind the target, appearing to impact just below.

If it's called below the target, the shooter will increase elevation, the result of which will raise the trajectory, and if there is grass just a few meters further out, no impact will be visible.

The correct call is to decrease elevation, as the bullet passed just over the top.

This can be illustrated by calculating the change in drop every two meters from 2 miles for the cartridge.

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DS Ds J

Some questions I have been wondering about - my terminology might be crooked ;)

- At what angle does the bullet engage the target?

- Is the angle of take-off equal to the angle of impact?

- Does the bullet travel point-first all the way, or does it it fall parallel to the barrel during the final stages of flight?

41 414gates OP

As far as I understand

- At what angle does the bullet engage the target?

This depends on spin. It is said that the nose of the bullet doesn't follow the trajectory if there is too much spin, then others say it is not true. What is observable is that the bullet is on a steep downward trajectory at ELR distance, and you can see this when the bullet impacts the steel, there is very little relative motion of the plate, and dust raised at the foot of the target. When there is dust at the foot of the target, and the plate hasn't moved, it's assumed to be a miss, but in fact it is usually indicative of an impact. Target indicators are a big help.

- Is the angle of take-off equal to the angle of impact?

No, because if you shoot from an elevated position, your barrel angle may be near horizontal, but when the bullet gets to target, it's falling quite steeply.

- Does the bullet travel point-first all the way, or does it it fall parallel to the barrel during the final stages of flight?

The bullet nose should follow the trajectory path. There is debate as to wether it does or does not, and why or why not. I don't know how it's falling, I just know that at ELR distance, it's falling out of the sky like a rock, with only a few hundreds of fps velocity left.

If a bullet tumbles in flight due to rotational instability [ insufficent twist ], it's a disappearing shot, you won't see where it impacts unless you're shooting over water or desert sand, because it's going to come down long before it gets near the target.

TR Tripodmvr

240 MOA = 4 degrees. The angle will then be greater at 2 miles.

DS Ds J

The bullet nose should follow the trajectory path. There is debate as to wether it does or does not, and why or why not. I don't know how it's falling, I just know that at ELR distance, it's falling out of the sky like a rock, with only a few hundreds of fps velocity left.

Would it be possible to test that ie shooting into a large piece of wood, or something similar?

OA oafpatroll

The idea of a spinning bullet not being aligned to it's trajectory doesn't make sense to me.

41 414gates OP

This is what the expert has to say.

How bullets fly.

22 223

May I suggest reading the works of Bryan Litz. He is the chief ballistician at Berger bullets and has done a lot of empirical testing at long range.