AB Mobile zero atmosphere

_Raining

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It would be nice if it was available in DA but w.e.

I enable zero atmosphere (I played around with google calcs and came up with 2000 DA can be replicated with 29.26 inHg, 75 deg F, 50% Humidity {Pressure is absolute is enabled}). I set my zero range to 1000 yards. I hit done. Click the Sierra Matchkling profile that I just modified. I change DA to 8000 and my adjustment for 1000 yards is 0. I change DA to -2000 and again, adjustment for 1000 yards is 0.

Zero 1000 yards, Enable Zero Atmosphere, approx 2000 DA, change DA to -2000/8000 go to trajectory for 1000 yards and scroll down to 100 yard adjustment:
-2000 DA, 100 yard adjustment is D9.0
8000 DA, 100 yard adjustment is D7.8

Zero 1000 yards, Disable Zero Atmosphere, change DA to -2000/8000 go to trajectory for 1000 yards and scroll down to 100 yard adjustment:
-2000 DA, 100 yard adjustment is D9.0
8000 DA, 100 yard adjustment is D7.8

I figured a Zero Atmosphere would be for a situation where (for some reason) I zero my rifle @ 1000 yards at 800 DA and the next range trip the DA is 2000, with the Enable Zero Atmosphere enabled and set to the equivalent of 800 DA, then it would know to provide an adjustment when shooting in a DA of 2000. But the data for the 1000 yards is always 0.0 and the adjustment for any of the other ranges is the same for the feature being enabled vs disabled.

Am I misunderstanding what zero atmosphere is for?
 

Near miss

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Steel head

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In ballistic AE I use it mainly because my speed is relative to temp and if I get my temp offset right it compensates if I zero at 40 degrees and am shooting at 90 degrees.
At 100 yards it’s worthless but at distance it does seem to help if your powder changes speed more than than the common temp stable powders.
 

Near miss

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In ballistic AE I use it mainly because my speed is relative to temp and if I get my temp offset right it compensates if I zero at 40 degrees and am shooting at 90 degrees.
At 100 yards it’s worthless but at distance it does seem to help if your powder changes speed more than than the common temp stable powders.
You are referring to MV table / powder temp table?
Also atmospherics on their own affect flight path.
 

_Raining

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You are referring to MV table / powder temp table?
Also atmospherics on their own affect flight path.
I don't think Ballistics AE has a MV vs Temp function like AB does. Though the numbers did change when I gave it a 1000 yard zero and had the current atmospherics different from the zero atmospherics, thought I think it was only like .14 mils for a diff of like 25 degrees, not sure how correct that is. I always thought temp effected drag a lot.
 

Steel head

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I don't think Ballistics AE has a MV vs Temp function like AB does. Though the numbers did change when I gave it a 1000 yard zero and had the current atmospherics different from the zero atmospherics, thought I think it was only like .14 mils for a diff of like 25 degrees, not sure how correct that is. I always thought temp effected drag a lot.
It has a correction value you enter.
fps per degree.
 

_Raining

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It has a correction value you enter.
fps per degree.
I don't see that in my app. I don't see a way to set it to DA either but according to the internet you can. Maybe I am just retarded.
 

Steel head

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I don't see that in my app. I don't see a way to set it to DA either but according to the internet you can. Maybe I am just retarded.
Temp correction is in the reloading area of the data inputs area.

Da is set in settings then in the atmosphere input area.
 

Steel head

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I don't see that in my app. I don't see a way to set it to DA either but according to the internet you can. Maybe I am just retarded.
Temp correction is in the reloading area of the data inputs area.

Da is set in settings then in the
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2ACF51BE-EA1C-4B28-B19A-1BFA23199317.png
 

TacticalDillhole

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You realize a 100 yd zero will have pretty much no change in different conditions. The zero atmosphere is for the other than 100 yd zero folks......hunters or ELR guys.

also, I e said this many times, DA is for field cards. When using an app you should use pressure, temp and RH (could alsonkeave at 50 and ignore it). A given DA can be calculated in many different ways using these variables and saying DA is the same regardless is wrong. A high temp low pressure DA is different than a high pressure low temp DA on ballistics even though they are both 2500ft.
 

Dthomas3523

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You realize a 100 yd zero will have pretty much no change in different conditions. The zero atmosphere is for the other than 100 yd zero folks......hunters or ELR guys.

also, I e said this many times, DA is for field cards. When using an app you should use pressure, temp and RH (could alsonkeave at 50 and ignore it). A given DA can be calculated in many different ways using these variables and saying DA is the same regardless is wrong. A high temp low pressure DA is different than a high pressure low temp DA on ballistics even though they are both 2500ft.
This. Zero atmosphere isn’t for the people who should be using 100yd zero. Basically ELR where you have too much built in cant for closer zero.

Otherwise, there is no good reason not to use 100yd zero.

And to reiterate, if using an app DA is not the way to go.
 

_Raining

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You realize a 100 yd zero will have pretty much no change in different conditions. The zero atmosphere is for the other than 100 yd zero folks......hunters or ELR guys.
I understand that, I just wanted to play with the numbers so see how much of an effect it can have which is why I chose 1000 yard zero. But the numbers did not change so either I am doing something wrong or that feature is disabled but still appears on the screen.

also, I e said this many times, DA is for field cards. When using an app you should use pressure, temp and RH (could alsonkeave at 50 and ignore it). A given DA can be calculated in many different ways using these variables and saying DA is the same regardless is wrong. A high temp low pressure DA is different than a high pressure low temp DA on ballistics even though they are both 2500ft.
Noted. I'll need to refresh myself on pressure, IIRC it is absolute vs station pressure and you need to configure your kestrel properly to use the one that ignores altitude? IDK. I have some reading to do.
 

TacticalDillhole

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I understand that, I just wanted to play with the numbers so see how much of an effect it can have which is why I chose 1000 yard zero. But the numbers did not change so either I am doing something wrong or that feature is disabled but still appears on the screen.


Noted. I'll need to refresh myself on pressure, IIRC it is absolute vs station pressure and you need to configure your kestrel properly to use the one that ignores altitude? IDK. I have some reading to do.
Absolute and station pressure are the same thing, they are true uncorrected pressure. What you dont want to use is Barometric pressure which corrects local pressure for sea level.

Its really easy on your kestrel to do. Assuming you are using a 5700 elite, on the ALTITUDE Screen make sure Ref pressure is 29.92. On the Baro screen, make sure Ref alt is 0. Thats it.

Edit to add i almost forgot something important, make sure that in the settings menu for these screens that the sync baro and syn alt functions are off.
 
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