Android app and aerodynamic jump?

[jcampbellsmith]

Bryan

When do you plan to incorporate aerodynamic jump in the Android app calculations?

Thanks

JCS

 

[DocUSMCRetired]

We do not currently have a completion time for this update, the development team is working on it, as well as some other things like updating the bullet library.

 

[jcampbellsmith]

We do not currently have a completion time for this update, the development team is working on it, as well as some other things like updating the bullet library.

Thanks for the update. Best regards JCS

 

[jcampbellsmith]

We do not currently have a completion time for this update, the development team is working on it, as well as some other things like updating the bullet library.

Bryan

Any update on this one?

Thanks

JCS

 

[jcampbellsmith]

We do not currently have a completion time for this update, the development team is working on it, as well as some other things like updating the bullet library.

Bryan
Any progress on this feature?
Thanks
JCS

 

[DocUSMCRetired]

My apologies, but I do not have a release date for the next update at this time.

 

[jcampbellsmith]

My apologies, but I do not have a release date for the next update at this time.

I was shooting yesterday in a 15 mph cross wind at 3 o'clock at a gong at 400 yards. Back home the online calculator predicted a 0.6 MOA aerodynamic jump. It would have been handy to access that data in the field.

Regards

JCS

 

[bigngreen]

I use Applied ballistics over all but if I'm concerned about jump I use Strelok pro, only app that I'm aware of that currently has it.

 

[jcampbellsmith]

I use Applied ballistics over all but if I'm concerned about jump I use Strelok pro, only app that I'm aware of that currently has it.

Thanks, I've spent a fair bit of time and money learning to drive the Applied Ballistics App, so I'm loathe to start over again and buy another App.

Regards

JCS

 

[DocUSMCRetired]

All of our programs, except AB for Android has it. Including AB in iPhone. We are currently working on getting it integrated and running on the app at this time along with some other updates.

 

[jcampbellsmith]

All of our programs, except AB for Android has it. Including AB in iPhone. We are currently working on getting it integrated and running on the app at this time along with some other updates.

Thanks, I'm looking forward to the update. Best regards JCS

 

[SierraCJ5]

Please excuse my ignorance, but what is "aerodynamic jump"?

 

[jcampbellsmith]

Please excuse my ignorance, but what is "aerodynamic jump"?

From another thread:

There seems to be some confusion here on terminology.

Aerodynamic Jump (AJ) is usually discussed as being the vertical component of cross wind deflection. This is sometimes mistakenly referred to as crosswind jump. In a crosswind scenario, the aerodynamic jump is a systematic and predictable function of bullet stability and crosswind speed.

All mention of bullet imbalance and misalignment being related to dispersion is correct. However, the mechanism by which a bullet disperses from these things is called lateral throw-off. It's an inertial (mass properties) thing, not aerodynamic. So in the case of no crosswind, if you fire an imbalanced or 'off-axis' bullet, it will exhibit lateral throw-off at the muzzle which will establish some yaw. During the several precession cycles it takes to dampen the yaw is where AJ occurs as a result of the bullet being launched with some yaw rate.

So there are multiple ways for AJ to occur; either from the bullet entering a crosswind, or as a reaction to lateral throw-off in a random direction.

-Bryan

Regards

JCS

 

[SierraCJ5]

Please excuse my ignorance, but what is "aerodynamic jump"?

From another thread:

There seems to be some confusion here on terminology.

Aerodynamic Jump (AJ) is usually discussed as being the vertical component of cross wind deflection. This is sometimes mistakenly referred to as crosswind jump. In a crosswind scenario, the aerodynamic jump is a systematic and predictable function of bullet stability and crosswind speed.

All mention of bullet imbalance and misalignment being related to dispersion is correct. However, the mechanism by which a bullet disperses from these things is called lateral throw-off. It's an inertial (mass properties) thing, not aerodynamic. So in the case of no crosswind, if you fire an imbalanced or 'off-axis' bullet, it will exhibit lateral throw-off at the muzzle which will establish some yaw. During the several precession cycles it takes to dampen the yaw is where AJ occurs as a result of the bullet being launched with some yaw rate.

So there are multiple ways for AJ to occur; either from the bullet entering a crosswind, or as a reaction to lateral throw-off in a random direction.

-Bryan

Regards

JCS

Thank you, sir.

 

[jim_k]

IN the field, if you don't have your app, just calculate the wind drift with the formula: [number of yard in 100's] x crosswind component in MPH, divided by the bullet's drift constant, usually 15 for a long-range bullet out to about 750 yards. So 4 x 15 divided by 15 is 4 MOA. Divide that by 10, and you get 0.4 MOA, which at 400 yards is about 1½ inches. There you go! This vertical effect causes bullet impact to be high if wind is from the right, and to be low if wind is from the left. Your wind is 3:00, so aim 1½ inches low. There's also an east-west coriolis effect, not much at 400 yards, but the app has it, if you enter direction of the shot. Impact high when shooting east, and low when shooting west. Of course, the usual spinning plate coriolis for northern hemisphere, maybe 1½-2 inches to rt of POA at 400. Don't leave home without your app.

 

[avidflyer]

IN the field, if you don't have your app, just calculate the wind drift with the formula: [number of yard in 100's] x crosswind component in MPH, divided by the bullet's drift constant, usually 15 for a long-range bullet out to about 750 yards. So 4 x 15 divided by 15 is 4 MOA. Divide that by 10, and you get 0.4 MOA, which at 400 yards is about 1½ inches. There you go! This vertical effect causes bullet impact to be high if wind is from the right, and to be low if wind is from the left. Your wind is 3:00, so aim 1½ inches low. There's also an east-west coriolis effect, not much at 400 yards, but the app has it, if you enter direction of the shot. Impact high when shooting east, and low when shooting west. Of course, the usual spinning plate coriolis for northern hemisphere, maybe 1½-2 inches to rt of POA at 400. Don't leave home without your app.

if the wind is at 3 oclock that right to left wouldnt it be aim high?

 

[jim_k]

Wind from the right will cause POI to be high and left, so aim lower with wind from the right. "Don't leave home without your app" is my take-home message, in any case.

 

[avidflyer]

gotcha, read it to fast....

 

[jim_k]

I envision a sloped line running from high/left to low/right, sloped at a 1:10 slope. I dial for basic elevation, then hold off for wind. If the hold-off is to the right, I imagine my crosshairs following that sloped line, and when holding to the right, I automatically let the crosshairs go lower. When the wind is from the left, I follow the imaginary sloped line as it goes left and upward. That ingrains the habit, so as not to have to think about it. For me, less cerebration is preferable, since cerebrating happens slower as one ages - ahem! I don't do any calculations. The sloped line is 1:10 no matter the distance, for anything I shoot at.
Jim

 

[jcampbellsmith]

All of our programs, except AB for Android has it. Including AB in iPhone. We are currently working on getting it integrated and running on the app at this time along with some other updates.

Any date for this long awaited update?

Thanks

JCS