Not sure if this is the correct sub-forum to place this in, but here we go.
I am just getting into long(er) range shooting. Have been shooting rifles for decades, but mainly just hunting rifles with duplex reticles and Kentucky windage/elevation guesses. That said - I am loving the science of the longer range shooting. I read recently about aerodynamic jump/drag (AJ/D) and was wondering if it applied to a situation I had recently.
Hunting prairie dogs we mainly use a .17 hmr. 2 of the 3 days we hunted this year were extremely windy, 20-30 one day, 35-40 another. First day was pretty calm, maybe a 5-10 crosswind.
First day, the .17 was shooting POA/POI with the calm crosswind (generally a 90 degree wind, sometimes 3/4 value). In the high wind days we were seeing high left POI with a R->L wind and low right POI with a L->R wind.
I read this thread: https://www.snipershide.com/shootin...d-on-elevation-aerodynamic-jump-drag.6795073/
Generally seemed like AJ/D seemed like a minor factor, mainly to be ignored.
Finally to my question, with the terrible BC of the .17 hmr (we shoot 17g hornady vmax) and the extreme winds - would that be enough to account for AJ/D being what we were dealing with? Does a worse BC have any effect on increasing the effects of AJ/D? Also, as wind gets much higher I assume there would be a noticable increase in AJ/D? I am guessing it would be a linear increase? Guessing the above referenced thread is generally speaking about bullets with high BC so that it maybe diminishes the role to which AJ/D affects them.
My thoughts are that it might be, but I haven't paid that much attention before - just always assumed missed like that were me somehow. This year I noticed a very consistent pattern and the dope (once we found the problem) was very repeatable. This year I paid a lot more attention to what was happening and possible reasons for why, rather than just sending rounds without thinking about them. In general I am wanting to believe the bullet like I have read to do and what I was seeing certainly seemed to line up with what aerodynamic jump/drag would cause, but I am not sure if the science of it works out.
I am just getting into long(er) range shooting. Have been shooting rifles for decades, but mainly just hunting rifles with duplex reticles and Kentucky windage/elevation guesses. That said - I am loving the science of the longer range shooting. I read recently about aerodynamic jump/drag (AJ/D) and was wondering if it applied to a situation I had recently.
Hunting prairie dogs we mainly use a .17 hmr. 2 of the 3 days we hunted this year were extremely windy, 20-30 one day, 35-40 another. First day was pretty calm, maybe a 5-10 crosswind.
First day, the .17 was shooting POA/POI with the calm crosswind (generally a 90 degree wind, sometimes 3/4 value). In the high wind days we were seeing high left POI with a R->L wind and low right POI with a L->R wind.
I read this thread: https://www.snipershide.com/shootin...d-on-elevation-aerodynamic-jump-drag.6795073/
Generally seemed like AJ/D seemed like a minor factor, mainly to be ignored.
Finally to my question, with the terrible BC of the .17 hmr (we shoot 17g hornady vmax) and the extreme winds - would that be enough to account for AJ/D being what we were dealing with? Does a worse BC have any effect on increasing the effects of AJ/D? Also, as wind gets much higher I assume there would be a noticable increase in AJ/D? I am guessing it would be a linear increase? Guessing the above referenced thread is generally speaking about bullets with high BC so that it maybe diminishes the role to which AJ/D affects them.
My thoughts are that it might be, but I haven't paid that much attention before - just always assumed missed like that were me somehow. This year I noticed a very consistent pattern and the dope (once we found the problem) was very repeatable. This year I paid a lot more attention to what was happening and possible reasons for why, rather than just sending rounds without thinking about them. In general I am wanting to believe the bullet like I have read to do and what I was seeing certainly seemed to line up with what aerodynamic jump/drag would cause, but I am not sure if the science of it works out.
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