Kestrel 5700 Elite Not Lining Up - what settings do you guys have enabled/disabled?

[Bulldog Firearms]

I've been having some issues with my Kestrel last couple of matches. Figured it was something I was doing. Maybe it still is.

Velocity is gathered from a Magnetospeed.

My Kestrel is giving 6.1 Mils to 1k when in actuality it is 5.6. Basically high impacts from 500 to 1000 (as far as I shot).

Stuck my atmospherics and bullet data into JBM ballistics and took 4th place at the local match even with some major brain farts on my end. Was smashing the watermark on the steel I painted leading up to the match using the JBM data.

Have I enabled or disabled something that is screwing me up?

Any help would be appreciated.

 

[Dthomas3523]

I keep spin drift off, and I think latitude set to 1 so there’s no coriolis. Using AB custom curve for 108 eld and lines up to 1k.

7.4 mils, but we are only a few hundred above sea level and under 4k DA.

Something I did the other day that did something similar to your problem:

I was messing around with kestrel at home and locked the environment instead of having it on real time. Forgot to unlock it. Had it locked at 100 degrees and was shooting in 60. I was around .2 mil high at 400. So, this might be your issue too.

 

[Kestrel Ballistics]

Have you done the MV calibration?

 

[Raufoss]

I've never turned off anythig and data lined up perfectly..

The only thing you need to make sure you check is when you create a target , make sure you remove the target speed that they automatically imput.

 

[Bulldog Firearms]

Have you done the MV calibration?

I have not attempted to calibrate muzzle velocity. Something that has been spoken on here a lot, if you're getting your velocity from a trusted source, IE, magnetospeed you shouldn't mess with velocity.

 

[JLP.Payette]

I have not attempted to calibrate muzzle velocity. Something that has been spoken on here a lot, if you're getting your velocity from a trusted source, IE, magnetospeed you shouldn't mess with velocity.

I had the same problem and did a muzzle velocity calibration. My Magnetospeed says 2780 and the calibration came up with 2810. I used the 2810 and my Dope lines up perfectly.

 

[seansmd]

I have not attempted to calibrate muzzle velocity. Something that has been spoken on here a lot, if you're getting your velocity from a trusted source, IE, magnetospeed you shouldn't mess with velocity.

@Diver160651 helped me with this for the first time, I had magnetospeed for my ammo at 100, used Kestrel AB to dial to the 500 target, adjusted based on him on the sighting scope which required adjusting my elevation. Since I was using the custom curve from hornady 140ELDM I adjusted up the MV until the Kestrel aligned with the elevation we had locked in. Then set the Kestrel to 1000y target and it was money. It was then accurate to all 1k and less targets. Magnetospeed has an error margin just like anything, and the AB curve needs to be tweaked. My magneto was slower than Kestrel AB and all the solvers I aligned my real dope to after this process, Hornady 4dof, Sterlok, BallisticArc, in hind sight it was a very simple process.

 

[Diver160651]

I have not attempted to calibrate muzzle velocity. Something that has been spoken on here a lot, if you're getting your velocity from a trusted source, IE, magnetospeed you shouldn't mess with velocity.

That’s not true... look I made a joke..

I have to say a lot of people kind of miss understand the basics. First you need to have an absolute zero or known offset, good group, fair SDs and have to make sure that your range is absolutely certain. You might be surprised to see just how many ranges have the target off slightly.

Second thing to fundamentally understand, is Drag, expressed as a BC value, takes time to scrub speed.

For most long range cartridges, 300 -600y the variable that has the greatest impact is velocity. If you’re off several inches and over work at the BC value, you’ll still have issues further down range. Once your near rage drop is centered, You may run out to the edge of transonic and tune the BC. Doppler or custom curves may need the programs DK or other modifier changed.

If you do this correctly almost every program out there will lineup from zero to into the first part of trans.

Unfortunately in a lot of people overwork the BC and I never realize because they’re not tracking intermediate stops from zero passed a 1000

 

[Kestrel Ballistics]

I have not attempted to calibrate muzzle velocity. Something that has been spoken on here a lot, if you're getting your velocity from a trusted source, IE, magnetospeed you shouldn't mess with velocity.

Kestrels have 2 functions built in to true the calculation to your rifle/scope performance. MV calculation for supersonic distances and Drop Scale Factor for Transsonic distances. If you have errors in your solution, that should be the first place you go.

 

[LastShot300]

I have not attempted to calibrate muzzle velocity. Something that has been spoken on here a lot, if you're getting your velocity from a trusted source, IE, magnetospeed you shouldn't mess with velocity.

 

[plidenbrock]

I've always preferred to manually calculate my solutions, but as I've fiddled with the Kestrel Elite there have been a few things that stick out to me....

As noted above multiple places, within the supersonic range of the weapon, MV is the place to start. (b.c. is more relevant at trans and sub ranges). To that end, one must understand that the atmospherics present when you obtain your MV may not be identical the next time you need ballistic info. Decreased station pressure, even a warm receiver (sitting in the sun for example) can increase MV enough that the kestrel's solution will be too high.

Therefore, on the Kestrel there is a function which allows your MV to change with the atmospherics (temp most specifically). So I'd make sure your mv / temp curve function is turned ON. NOTE: One problem that I had when I was entering my temp/MV curve data into the phone app was that one of the fields read "0". I assumed that since the field was blank, it would ignore it. Oops. Fixed it and the MV / temp curve has corrected much closer.

Also as noted above, make sure that your environmental is turned to "Live" rather than "Locked". It almost got me once, the only reason I caught it is because I had JBM tables that suggested the Kestrel was wrong.

Another thing to double check is your barrel twist entry. Cross-winds can provide aerodynamic jump solutions that cause problems if the twist handedness is off or if your wind capture was goofed somehow.

It's possible you ran warm-up rounds or left the receiver in the sun or the ambient temp (and therefore ammo temp) was higher than your kestrel knew, leading to a higher MV than the MV the kestrel was working with. So it gave you more correction, when with a higher MV, less elevation was necessary.

Just some ideas for your consideration.

 

[Bulldog Firearms]

I haven't been out to shoot again but going to try again on Wed or Thursday. Will see if I can't get this thing trued up. I appreciate all the feedback.

 

[Dthomas3523]

I've never turned off anythig and data lined up perfectly..

The only thing you need to make sure you check is when you create a target , make sure you remove the target speed that they automatically imput.

You don’t need to get rid of the target speed unless you’re going to shoot a mover.

The lead for the mover is separate and doesn’t influence your normal dope.

 

[seansmd]

You don’t need to get rid of the target speed unless you’re going to shoot a mover.

The lead for the mover is separate and doesn’t influence your normal dope.

When I was looking at my data it did seem to affect the suggested horizontal dope, was I looking at it wrong?

 

[Dthomas3523]

When I was looking at my data it did seem to affect the suggested horizontal dope, was I looking at it wrong?

Spin drift not turned off.

 

[seansmd]

@Dthomas3523 I must have been on crack, I just verified, changed only TGT, TS to 2mph and no change in horizontal hold.

FYI, I do have Spndft on.

 

[Dthomas3523]

@Dthomas3523 I must have been on crack, I just verified, changed only TGT, TS to 2mph and no change in horizontal hold.

FYI, I do have Spndft on.

Spin drift will give you difference in horizontal hold. Typical the difference is smaller than most people are capable of holding inside 1200yds or so. So most people turn it off unless they are shooting ELR.