Bummer about Kestrel-Applied Ballistics

H

HairHunter

Private
Full Member
Minuteman
Mar 11, 2004
34
0
65
Tacoma Wash.
#1
Just figured out my new Kestrel with Applied Ballistics does not compensate for velocity@temp. without manual input.
I got my 338 Edge dialed in with the Kestrel at 1200 meters,2835 velocity,80 degree temp-working great.About a week later I am shooting,this day it's early morning and chilly 50 degrees. I am shooting high at all ranges. After playing with the new kestrel and reading the instruction booklet,I realize the velocity input does not change with temp change,it must be a manual change.
If you get your Kestrel set up for 70-80 degrees and then go hunting and have 30-40 degree weather, You are gonna be quite a ways off. Sent Bryan Litz an E-mail and no the AB. Kestrel does not change velocity@temp without manual input.Mr Litz said a good rule of thumb is .5 fps. change per temp degree for single base powder,and 1fps.change per degree with double base powder.
This seems to be close in my kestrel, but I need to shoot some more at longer range.
 
#6
Justinbaker,
Finally someone who is suprised too! I thought it would have the same options as the AB. mobile app. After you figure out your velocity@ temp variation,you just need to keep changing your entered velocity for each gun as temp changes.Wish it would have been included in the Kestrel program.
 
#7
HairHunter said:
Just figured out my new Kestrel with Applied Ballistics does not compensate for velocity@temp. without manual input.
I got my 338 Edge dialed in with the Kestrel at 1200 meters,2835 velocity,80 degree temp-working great.About a week later I am shooting,this day it's early morning and chilly 50 degrees. I am shooting high at all ranges. After playing with the new kestrel and reading the instruction booklet,I realize the velocity input does not change with temp change,it must be a manual change.
If you get your Kestrel set up for 70-80 degrees and then go hunting and have 30-40 degree weather, You are gonna be quite a ways off. Sent Bryan Litz an E-mail and no the AB. Kestrel does not change velocity@temp without manual input.Mr Litz said a good rule of thumb is .5 fps. change per temp degree for single base powder,and 1fps.change per degree with double base powder.
This seems to be close in my kestrel, but I need to shoot some more at longer range.
Click to expand...

HH, I was working on the same thing with my apps last night and if I change the Temp the MOA changes but then you have to Chrono your Ammo at that Temp so you can Add the new FPS data, The MOAs change with the TEMP and when you Add the higher FPS they change again and this Guy in this Video had me crunching numbers till the early hours, and I also found one of my Apps that when I changed the Ammo Temp nothing happend so Im gonna write to em and see if they can fix that, But really it should AUTO update the FPS too but it dont, Like you that has to be done manually with the Chrono,

good luck Mate, John

https://www.youtube.com/watch?v=uFrOwyRbDGA&list=PLdTcHB0tfA3T5W_IjUvy30QUPrXRDLQDn
 
#8
According to the Maths on the Video a 20*F rise in temp and with the Ammo rise to match that 20*f gives a .308 at 2600fps @ 60*f TO 80*F causes the FPS to Rise to 2652 fps which is a rise of 2.6fps per Degree of F*,

hope this helps,, john
 
#9
I just can't see this being any fun if technology does it all for you. I enjoy building dope in all conditions (which also gives you practice in those conditions) instead of relying on gadgets to give approximations.
 
#11
.284 said:
My kestrel with the Horus software allows you input different velocities for different temps and then extrapolates a velocity from that info for solutions. I am surprised that the applied ballistics version doesn't do that too
Click to expand...

Imputting differant Velocities is'nt the problem what it does'nt do is when you change the Ammo Temp it does'nt change the FPS from the base line FPS IE when you have an FPS of 2600 and you add 20*F to the ammo temp it does'nt change the FPS to 2652 which is about the right speed for the .308 with that Temp increase,

maybe Bryan might know the Answer to this one, MAYBE it does'nt have to change the numbers of the FPS as it has already compensated for that but reducing the amount of MOA to reach the Target??

john
 
#12
By popular request,
This feature has been added to the AB software.

There is a procedure for flashing software updates and we're working on generating instructions to do this.

You'll need the kestrel to be in communication with a PC either via BT or serial cradle in order to upgrade.

Look for an announcement from Kestrel in a week or so regarding this firmware upgrade.

We're learning that putting out 'good' software is a balance between rich feature set vs. simplicity and ease of use. The implementation of these new features is done in a way which allows you to use them if you want, but won't force you to if you don't.

Thanks for the continued feedback which helps us to continually improve the AB product line.

-Bryan
 
#14
BryanLitz said:
By popular request,
This feature has been added to the AB software.

There is a procedure for flashing software updates and we're working on generating instructions to do this.

You'll need the kestrel to be in communication with a PC either via BT or serial cradle in order to upgrade.

Look for an announcement from Kestrel in a week or so regarding this firmware upgrade.

We're learning that putting out 'good' software is a balance between rich feature set vs. simplicity and ease of use. The implementation of these new features is done in a way which allows you to use them if you want, but won't force you to if you don't.

Thanks for the continued feedback which helps us to continually improve the AB product line.

-Bryan
Click to expand...

Brilliant Job Bryan, WTG, I wont ask how you worked it out so fast But thats Impressive to say the Leased

Blessin's John
 
#15
My biggest "issue" with the AB thus far is separate profiles for 300wm vs. 308...It's a little confusing. Had to get the computer program/cable to really get some clarity.

Temperature was kind of meh, IMO, because once you shoot LR enough, you just make the adjustment manually...I guess it's a preference thing.

I'm quite pleased with my AB...More-so than I initially thought I would.

Keep up the good work!
 
#17
Bryan,

I have another question regarding the AB Kestrel. When I have zero wind plugged in, my 100 yard dope reads zero as expected. If I put in a 10 mph cross wind, the hundred yards dope shows .1 or -.1 depending on 3 or 9 o'clock. 20 mph shows .2 or -.2. Now this may be correct, but none of my other programs calculate this, shooter, etc. Any light you can shed on this? Thanks so much.
 
#18
boss said:
Bryan,

I have another question regarding the AB Kestrel. When I have zero wind plugged in, my 100 yard dope reads zero as expected. If I put in a 10 mph cross wind, the hundred yards dope shows .1 or -.1 depending on 3 or 9 o'clock. 20 mph shows .2 or -.2. Now this may be correct, but none of my other programs calculate this, shooter, etc. Any light you can shed on this? Thanks so much.
Click to expand...

That cant be right because with a 308 that would be .2mrads or 0.7" inches, 15mph= 0.3mrads @1.1 inches and 20mph= 0.4mrads = 1.4"inches

John
 
#20
boss said:
Bryan,

I have another question regarding the AB Kestrel. When I have zero wind plugged in, my 100 yard dope reads zero as expected. If I put in a 10 mph cross wind, the hundred yards dope shows .1 or -.1 depending on 3 or 9 o'clock. 20 mph shows .2 or -.2. Now this may be correct, but none of my other programs calculate this, shooter, etc. Any light you can shed on this? Thanks so much.
Click to expand...

What you're seeing is the effect of aerodynamic jump. It's the vertical deflection of a pure crosswind. It's small, but real.

-Bryan
 
#21
I just switched over from the Horus to AB Kestrel. I'll get to confuse the hell out of myself all over again when I'm CONUS in a few weeks. It's incredibly comforting that Bryan is actually here on the Forum when issues like this arise; which was actually a consideration when I decided to switch over.
 
#22
Delta4-3 said:
I just can't see this being any fun if technology does it all for you. I enjoy building dope in all conditions (which also gives you practice in those conditions) instead of relying on gadgets to give approximations.
Click to expand...

I'm with you on this. I compare it to a child and basic math skills; can't build a solid foundation by using calculators. Just have to take the time, make the mistakes, and build a solid foundation that will serve you well regardless of the situation.
 
#26
Monmouth said:
I'm with you on this. I compare it to a child and basic math skills; can't build a solid foundation by using calculators. Just have to take the time, make the mistakes, and build a solid foundation that will serve you well regardless of the situation.
Click to expand...
My goal is putting rounds on target. My new 4500 with AB just made it faster and more consistent for me. To each their own...
 
#29
BryanLitz said:
What you're seeing is the effect of aerodynamic jump. It's the vertical deflection of a pure crosswind. It's small, but real.

-Bryan
Click to expand...

Yup,
Any helicopter person will know about this, gyroscopic momentum causes a movement 90 degrees to the force acting upon the gyroscope. So the +.1 or -.1 will depend on both the wind direction and the bullet rotation direction (RH or LH).

Jay
 
Last edited:
#30
Shot Angle w/Baro compensation

One other question, does the AB application have the ability to compensate for the barometric difference during high angle shots? i.e. I may have 29.92 inhg pressure at my rifle, but where the bullet will hit the pressure could be 29.62 inhg. I know we can't measure the actual pressure at the bullet impact altitude, but it can be approximated using simple trig (since you have distance and angle) and a standard baro table.

Jay
 
#33
BryanLitz said:
What you're seeing is the effect of aerodynamic jump. It's the vertical deflection of a pure crosswind. It's small, but real.

-Bryan
Click to expand...

How do I zero this effect out on my ballistics calculator when shooting to build dope? If, say 10mph from left causes my impact to shift +.1mil at distance, won't the opposite, a 10mph wind from right cause a -.1mil POI shift? How can I be sure my dope, and my variables used to extrapolate from, are correct?
^I hope I explained clearly enough that you can get the gist of my question and provide an answer. Thanks.
 
#34
I just purchased the ab kestel and I dont even know if I set it up correctly. I think I need another year at Ohio State to make sure I can use it..........after reading this thread, my head is spinning......
 
#35
Just talked to NK-Kestrel.They said the software update will be aprox. another month.He told me if you have the Bluetooth model,They can send the files to your computer,and then you can transfer the files to the Kestrel.
 
#36
Supergyro said:
How do I zero this effect out on my ballistics calculator when shooting to build dope? If, say 10mph from left causes my impact to shift +.1mil at distance, won't the opposite, a 10mph wind from right cause a -.1mil POI shift? How can I be sure my dope, and my variables used to extrapolate from, are correct?
^I hope I explained clearly enough that you can get the gist of my question and provide an answer. Thanks.
Click to expand...

Best to do your zero work in calm conditions. Not to sound tongue-in-cheek but I shoot early for calibration work as it's the calmest part of the day. Then I play with the wind afterward


Sent from my iPhone using Tapatalk - now Free
 
#37
You must log in or register to reply here.

Similar threads

9
Applied Ballistic custom curves
Replies
14
Views
369
Holliday
Holliday
Lowlight
Terminus Zeus - 6.5CM to 6.5PRC using Gravity Ballistics
Replies
7
Views
743
Baron23
Baron23
Milirad
Rifle Scopes Burris Eliminator 6 Accuracy Range Test Review
Replies
19
Views
8K
Eric B.
E
Rbb392
Getting started ballistic calculators
Replies
0
Views
293
Rbb392
Rbb392
C
Differential Equations and Ballistics?
Replies
9
Views
414
Cheetah
C
Top Bottom
Back
Home
Forums
Merch
Alerts