Originally Posted by verminator
On the subject of the rifleman's rule, does anyone have an explanation for why it doesn't work with airguns? The theory seems reasonable.
Yes, I can help you with that.. in fact you can prove it doesn't work to yourself which is far better than me just telling you it doesn't.
Ok here's the scenario I want you to calculate using the Rifleman's rule.
You have a rifle that is zeroed at 10 yards, you want to hit a 15mm target that is directly above you, but 10 yards away from the end of your barrel.
Where do you aim?
The rifleman's rule says you consider the horizontal distance to the target (this would be 0 - it's directly above you)
So you would aim in the same spot you would need to aim if the target was touching the end of your barrel. (according to the Rifleman's rule)
In this situation the Rifleman's rule would tell you that you need to aim above the 15mm killzone by the height of your scope in order to hit it.
That's not correct, what you would actually need to do to hit that target is aim a tiny bit low in the kill - a couple of mm. You might say - ah but this is just some weird situation you've chosen and the Rifleman's rule is generally correct. It isn't though, I could give you lots of examples where it's wrong. The reason it's wrong is that most of the shots in airgunning tend to be quite close and the rifleman's rule is spectacularly wrong at close range. (As that example should illustrate).
The bendy barrel thing.. that's just mad
The real reason does have something to do with Gravity (alot actually) but it isn't the effect of gravity on the barrel, it's the reduction in the effect of gravity on the horizontal trajectory that's important.