Data not lining up with kestrel

amork

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So I broke down and bought a kestrel 5700 elite and have been messing around with it a little bit this late summer and fall. I decided to use it on a new load for my .300wsm. 22" bartlein cf wrapped barrel 1:10"
-Norma case
-68.2 grains h-4831sc
-fed 215 primer
-190 berger vld

Off the magnetospeed I'm seeing an ES of around 8-10 and about 2890 fps.

I watched a bunch of videos on the kestrel and followed the instructions and shot my target at 985 yards to true my data. Upon shooting a few times at the target And getting consistent impacts I am confident this should be good data. When I type in my elevation on the kestrel, it is giving me 3105 as my trued velocity. I used the applied ballistics custom curves for the bullet. I know the range is correct. I've ranged the target over and over again and it's the same each time. We trued my buddies 7mm stw the same way and it's giving a believable trued muzzle velocity as well with accurate data. Anyone ever ran into this?
 
-How many shots at distance? On paper or steel? Are you able to resolve every single impact?

-How's your zero and zero offsets? How many rounds did you shoot to get the zero and zero offsets? What range did you zero?

-Are all your units set correctly in the Kestrel?

-Did you update all environmentals (unlock and swing kestrel around for a minute) or just update elevation?

-How did you establish scope height above bore?

-How many shots to get your MV? Was that done in the same general temperature as truing? If not, do you know how your powder is affected by temp swings?

-Are you certain there's not a "you" factor playing a role.

Seems like most of these kind of discrepancies have numerous players that all compound.
 
What scope is on this rifle?
How confident are you in this scope's adjustments being correct?
Have you re checked your zero after shooting / dialing at distance?
With my 5700 Ballistic Kestrel, my trued MV based on my scope elevation adjustment at 775 yards, was less than 1% different from my LabRadar MV.
 
-I'd say 10-12 shots at this distance on steel. Only ones that were a miss were because of wind and also a few finding the right elevation adjustment.
-my zero is rock solid, I've shot quite a few groups at 100 yards and I always go back and shoot a couple at 100 before going out in distance just to verify. It's always came back and this scope has always tracked. It's a nightforce atacr 5-25.
-units are correct, I verified that a couple times over.
-mv was done at a different time with warmer temps. I didn't think 4831-sc was to temp sensitive so didn't take that into consideration, not enough to cause 215fps of difference anyway.
-I guess there could be some of me involved in it but with the same exact setup except a stainless barreled 6.5prc on the same action/same scope/same stock, using the shooter app and the magnetospeed mv I didn't have any issues and I shot that at every distance from 100-1317 yards repetitively.

I'll look over all the settings again on the kestrel to verify your guys points because I have got to be missing something. There's no way a 300wsm with a 22" barrel and a 190 grain bullet could fly that fast.
 
I mean, if the kestrel is giving you a good solution, then really who cares what the MV says it is. At least imo, as far as being practical is concerned.

All the things that were already said could be it. The kestrel app will have the ability to add in temp sensitivity if you think it will help. It's never changed much for me.
Other things can be: minor scope tracking errors that compound, differences in atmosphere when you chrono'd compounded with other factors, like shooting in prone vs standing vs bench…which often can throw MV off without sound technique.

On another note of compounding errors, getting a accuracy range and getting a repetitive range are two different things. I'm assuming you have a quality rangefinder the distance but it's worth mentioning, as far as trouble shooting is concerned.
 
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How are your impacts at 4,5,6,7,800 with actual dope vs kestrel. It's doesn't really matter what velocity the kestrel needs to make your chart as long as your getting impacts on waterline. It's annoying but if your getting hits your getting hits.

I have a couple high velocity rifles that aren't anywhere close labradar to Kestrel but get water line hits at distance.
 
maybe youre doubling up and messing up when you enter your elevation? You shouldnt have to enter elevation if you enter your air pressure.
 
maybe youre doubling up and messing up when you enter your elevation? You shouldnt have to enter elevation if you enter your air pressure.
with the kestrel 5700 series, you don't enter any environmental data, it is reading it for you. It is a weather station and ballistic solver all in one.
 
Or i should say, let the kestrel take its readings and lock it. You shouldnt have to enter any environmentals if you let the kestrel do it
 
with the kestrel 5700 series, you don't enter any environmental data, it is reading it for you. It is a weather station and ballistic solver all in one.
I understand that, i use a kestrel too. He said he entered elevation on the kestrel. Maybe he is adding error?
 
Correction, I entered how many mils for the 985 yards, not "elevation"
I could be shooting in the dark here…. I don't use a kestrel but as far as I'm aware when your calibrate(true) your ballistic solver to your load you're either changing the BC or MV. Some give you the option to put in you scopes dialing error in a percentage of a MOA/MIL.(never used it but know it's a thing)

With my zeiss rf binos vortex fury ab, and strelok app I usually true the BC because I shoot with my labradar so I have a good idea what the true MV is. Once I get the bc trued the silver gives me good data as far as I can shoot at my spot(little over 960)
 
I could be shooting in the dark here…. I don't use a kestrel but as far as I'm aware when your calibrate(true) your ballistic solver to your load you're either changing the BC or MV. Some give you the option to put in you scopes dialing error in a percentage of a MOA/MIL.(never used it but know it's a thing)

With my zeiss rf binos vortex fury ab, and strelok app I usually true the BC because I shoot with my labradar so I have a good idea what the true MV is. Once I get the bc trued the silver gives me good data as far as I can shoot at my spot(little over 960)
He's not using a BC, he's using a custom drag model specific to his bullet. They are generally more accurate as long as your bullet is operating with the averages they use to parameter the results of the model for that bullet. For some, Litz has custom curves for specific people or rifles for the same bullet. So there's nothing to true as far as BC goes within super sonic.

For subsonic, which is not the OPs problem in this post, there will be another truing option/process called drop scale factor.

Chances are there are other compounding errors that have built up that have trued into the OPs data. It's really not a big deal imo.
 

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