.22 Headspace (or does it matter....)

[grauhanen]

Largest divergence between muzzle and target is about halfway there when you're tuned for that target's distance. Interesting how that works, eh? It's almost like the bullets' flight paths follow some kind of rules... I wonder if any of those rules might explain why it is only "about halfway there" and not "exactly halfway there"...

Shorty, it appears that your ideas are based on too much misguided theory. Unfortunately they don't reflect reality.

You refer to "some kind of rules" above. You seem to believe that one of them is that .22LR rounds self-correct as they fly toward the target. You say that some kind of force acts on rounds to reduce their rate of dispersion as they fly past the half-way point, that group size begins to shrink (in terms of MOA) once past about half-way to the target.

That is a misunderstanding of how things work. It's wrong. Bullets do not self-correct as they pass the halfway point and go down range to target. There is no force that causes a group to shrink in MOA size once beyond the halfway point up to the bullseye.

Surely you can't imagine that such ideas would find support among serious shooters. You would have to believe that you're the only one who is correct and everyone else is mistaken. If you could shoot more and theorize less you might avoid such wrong-headed ideas.

 

[barsik]

Shorty, it appears that your ideas are based on too much misguided theory. Unfortunately they don't reflect reality.

You refer to "some kind of rules" above. You seem to believe that one of them is that .22LR rounds self-correct as they fly toward the target. You say that some kind of force acts on rounds to reduce their rate of dispersion as they fly past the half-way point, that group size shrinks once about half-way to the target.

That is a misunderstanding of how things work. It's wrong. Bullets do not self-correct as they pass the halfway point and go down range to target. There is no force that causes a group to shrink in size beyond the halfway point up to the bullseye.

Surely you can't imagine that such ideas would find support among serious shooters. You would have to believe that you're the only one who is correct and everyone else is mistaken. If you could shoot more and theorize less you might avoid such wrong-headed ideas.

I think you may have misunderstood the principle of shorty's explanation. a properly tweaked rimfire tuner will be adjusted so that the bullets are leaving the barrel as the barrel is flexing upwards. this is crucial because of the typical velocity variation between rounds. faster bullets leave the barrel sooner, before the barrel has reached it's apex of upward flex. slower bullets leave later as the barrel is still flexing upwards and will have a slightly greater parabolic trajectory but will impact the target at the same point, even though their velocities are different. the round itself isn't self correcting, but the tuner is correcting for velocity difference in a very specific way. quite a clever solution actually.

 

[Williwaw]

Largest divergence between muzzle and target is about halfway there when you're tuned for that target's distance. Interesting how that works, eh? It's almost like the bullets' flight paths follow some kind of rules... I wonder if any of those rules might explain why it is only "about halfway there" and not "exactly halfway there"...

I'll bite ... I'm thinking it is 'about halfway there' because the bullet is slowing down. Set me straight if I'm wrong. Thanks Shorty.

 

[_Shorty]

I think you may have misunderstood the principle of shorty's explanation. a properly tweaked rimfire tuner will be adjusted so that the bullets are leaving the barrel as the barrel is flexing upwards. this is crucial because of the typical velocity variation between rounds. faster bullets leave the barrel sooner, before the barrel has reached it's apex of upward flex. slower bullets leave later as the barrel is still flexing upwards and will have a slightly greater parabolic trajectory but will impact the target at the same point, even though their velocities are different. the round itself isn't self correcting, but the tuner is correcting for velocity difference in a very specific way. quite a clever solution actually.

I think I broke him. He doesn’t seem to think about things anymore. All he does is argue now.

I'll bite ... I'm thinking it is 'about halfway there' because the bullet is slowing down. Set me straight if I'm wrong. Thanks Shorty.

Exactly. The ballistic trajectory would be a perfect parabola if we were shooting without the atmosphere, such as on the moon. If you shot on the moon the bullet's highest point between the muzzle and the target would be halfway there, if the muzzle and target were the same height off the ground anyway. But since we have the atmosphere to contend with, the ballistic trajectory is a parabola that's been skewed by bullet drag. That pushes the peak of the trajectory past the halfway point a bit. The parabola gets squeezed shorter and shorter the longer the bullet is in the air and slowing down.