Applied Ballistics App. - Curious output

[bpm990d]

Every once in a while I get stumped. I've been running Applied Ballistics for Android for as long as I can remember so I'm not a first time user, but I have encountered some weird behavior that is most likely attributed to user error, so really this is about helping me understand what I'm doing wrong. This is not about exterior ballistics, I'm just running simulations on the app.

I actually uninstalled the app to hopefully fix the issue, but it seems to persist. Basically my trajectory table is off by less than a minute at the zero distance.

Under the cartridge I select a zero range, say for instance 600 yards and then when I run the solver it shows the path in inches being 2" high at 600 yards. I have the elevation correction factor set to 1. I also have the zero height set to "0". Shouldn't the path be "0" at the zero distance? In the past, that always seemed to be the case. Something is causing an offset and I'm flummoxed about it. This happens when I use CDMs or BCs and regardless or zero range. Although the error does change depending on the zero range.

Any help would be appreciated.

B

PS- I don't have this issue when running the Point Mass Ballistics Solver 3.0 that came with Bryan's book, but

 

[adam]

If you change your twist direction from right to left you can see that the error becomes negative instead of positive, if you change the wind direction from 90 to 270 it also flips the sign, and if you change your twist rate you can see the error increase/decrease, and if you set wind speed to 0, it goes away. The solver is probably computing the drop, then adjusting the gun elevation angle to set the zero range, and then adding in aerodynamic jump. The solver is assuming that you have zeroed the gun with zero wind.

Maybe someone at applied ballistics can confirm.

 

[STOMP442]

I have noticed this as well. Even though I know I have a solid zero at 100 yards it always shows a click off either way. This doesn't seem to effect my down range calculations at all but it never shows zero at my zero range. Just one of those things I've learned to just shrug my shoulders at and move on. The problem I have been having lately is that the app keeps telling me that it failed to get current weather conditions. Been going on a couple weeks now.

 

[bpm990d]

Hmm, thanks for the heads up on that. I think it's probably related to coriolis and or aerodynamic jump. Only way I could get it to show "0" at the zero range was to set the wind to "0" at 3 O'Clock and turn off Coriolis. That seemed to get rid of the minor errors at my zero range.

It just seems a little counter intuitive to the way I think. If I zero my rifle at 200 Yards, my zero takes into account all that stuff, so I don't really need the data about aerodynamic jump and coriolis at my zero range, I just need to know it's zeroed. I do want it calculated into the tables for the other ranges though.

Anyways, I know there is a reason they do this, I'm not second guessing A.B. but I probably don't use it they way they designed it and I'm left scratching my head sometimes. I did download the A.B Analytics documentation, but I have not had a chance to dive into it. I know it's different software, but thought it might shed some light.

STOMP442, I don't have mine linked to a Kestrel so I can't help with that, but I do know that Bluetooth can be a pain in the neck to configure sometimes. Good luck getting it sorted out.

Thanks for both your replies, it did let me fix the issue.

B

 

[STOMP442]

Hmm, thanks for the heads up on that. I think it's probably related to coriolis and or aerodynamic jump. Only way I could get it to show "0" at the zero range was to set the wind to "0" at 3 O'Clock and turn off Coriolis. That seemed to get rid of the minor errors at my zero range.

It just seems a little counter intuitive to the way I think. If I zero my rifle at 200 Yards, my zero takes into account all that stuff, so I don't really need the data about aerodynamic jump and coriolis at my zero range, I just need to know it's zeroed. I do want it calculated into the tables for the other ranges though.

Anyways, I know there is a reason they do this, I'm not second guessing A.B. but I probably don't use it they way they designed it and I'm left scratching my head sometimes. I did download the A.B Analytics documentation, but I have not had a chance to dive into it. I know it's different software, but thought it might shed some light.

STOMP442, I don't have mine linked to a Kestrel so I can't help with that, but I do know that Bluetooth can be a pain in the neck to configure sometimes. Good luck getting it sorted out.

Thanks for both your replies, it did let me fix the issue.

B

I'm not running a Kestrel either just the app on my phone. It will usually pull the weather info in a matter of seconds and auto populate the altitude, pressure and temp fields in the app. Lately though its been taking about 20 seconds and then giving me a pop up that says it failed to get current weather conditions. My local range actually sits less than 2 miles away from the closet weather station located at the Airport. I'm not sure if there is something wrong with the weather station or the app at this point. Next time I go out of town I will have to check and see if it works.

 

[bpm990d]

I'm not running a Kestrel either just the app on my phone. It will usually pull the weather info in a matter of seconds and auto populate the altitude, pressure and temp fields in the app. Lately though its been taking about 20 seconds and then giving me a pop up that says it failed to get current weather conditions. My local range actually sits less than 2 miles away from the closet weather station located at the Airport. I'm not sure if there is something wrong with the weather station or the app at this point. Next time I go out of town I will have to check and see if it works.

Oh ok gotcha. I thought you were pulling it from a seperate device. I have not tried to sync the app to local weather but maybe I should give it a try. I really like AP Mobile, but have come across a few things that are annoying. I wish they had a robust manual to go along with it.

 

[STOMP442]

They have a user manual under the education tab on their site that covers most things.

Applied Ballistics Mobile User Manual - Applied Ballistics

appliedballisticsllc.com

 

[bpm990d]

They have a user manual under the education tab on their site that covers most things.

Applied Ballistics Mobile User Manual - Applied Ballistics

appliedballisticsllc.com

Hey that's fantastic. I didn't know it even exists!

 

[Flatfishhunter]

This is due to aerodynamic jump and occurs when you have wind set in the parameters. Set your wind speed to 0 in AB. Then you should find 0 in your path/MOA for your chosen zero range.

 

[Quickoz]

Thanks for answering that. Ive been wondering the same thing with the zero range.