.22lr Center-X Kestrel AB Inputs

[SkyScrapin]

I've had this iron in the fire for wayyyyy too long, and it's nearly coming to a head.

RimX
Bartlein Carbon .22lr 20" (padom special)
AI AICS - whenever the AXSR variant is complete and stop holding up my project
TT Diamond
Era-Tac adjustable Mount
and, LOL, S&B 3-27 DTII LLR-Mil

I've got a pile of Center-X, and for those of you shooting this stuff 300-400 yards, what do your Kestrel AB inputs look like?

Pics to come once she's all perdy and complete.

ETA: G1 BC appears to be .174. Can anyone verify?

 

[littlepod]

This is at Sea Level.

 

[b6graham]

I run a .132 BC and it works well

 

[littlepod]

Custom curve from AB for Center-X. I haven't used a flat BC in a long time, but when I did it was like somewhere .145 but it fluctuated with BC changing as velocity/distance.

 

[SkyScrapin]

Custom curve from AB for Center-X. I haven't used a flat BC in a long time, but when I did it was like somewhere .145 but it fluctuated with BC changing as velocity/distance.

How closely did it match up to actuals? Did you have to fudge velocity?

 

[acudaowner]

not that my results will be yours but I got for a 10 shot group
min 1087
max 1099
average1093
sd of 3.7 and this for a group at 82 feet
the middle row was the lapua center x the left groups were sk red box and the right was eley practice not the greatest groups of my life but it is what it is .

good luck with yours after shooting the sk it took my gun a few shots I guess its to settle in with the different ammo the same thing happened when I switched over to the eleys after these the practice ammo shot some pretty nice groups though its sd numbers were much higher
eley's practice
10 round group
those on paper
min 1059 max 1149 aver. 1100 sd 23.3 second 10 round group was min 1062 max 1116 aver. 1098 sd 16.4 and in case you care the sk red box shot
min 1079 max 1098 av 1091 sd 6.7
good luck with yours hope they work well for you I think its nice ammo if you can find it .

 

[littlepod]

How closely did it match up to actuals? Did you have to fudge velocity?

Nope.

Shot out to 450 yards across different places. Kestrel would update the data based on environmentals but it has been spot on.

 

[drglock]

I entered all my stuff on my phone app and then transferred it to my Kestrel. Then did the DSF with my Center X and my RimX.
Did the DSF out to 275yds.
this is my inputs.
Velocity out of my 18” Green Mountain is anywhere from 1118fps @ 97* to 1093fps @ 42*

 

[Dthomas3523]

If you use the DSF function to true, your inputs don’t have to be perfect. I trued my rifle with sk standard plus over a year ago with DSF.

4,000 rounds of this lot later, dope is still perfect.

 

[SkyScrapin]

If you use the DSF function to true, your inputs don’t have to be perfect. I trued my rifle with sk standard plus over a year ago with DSF.

I did this with a center fire rifle and my results were all sorts of backwards. Are you entering dope, then going into DSF to adjust the correction at given yardage and mils actual? What’s your process?

 

[Dthomas3523]

I did this with a center fire rifle and my results were all sorts of backwards. Are you entering dope, then going into DSF to adjust the correction at given yardage and mils actual? What’s your process?

With centerfire, did you only use DSF in subsonic ranges?

You also have to make sure the inputs are in specific order.

 

[SkyScrapin]

With centerfire, did you only use DSF in subsonic ranges?

You also have to make sure the inputs are in specific order.

View attachment 7491998

Thanks boss. Good stuff.

Yes, I jacked with DSF after playing with velocity in the center fire supersonic stuff. Didn’t know how to true for a subsonic round though. That’s easy enough!

 

[Near miss]

How closely did it match up to actuals? Did you have to fudge velocity?

Does this help?

Kestrel 5700 vs 5700 Elite Drag model

Hi, Upgraded my Kestrel to Elite and thought to make a quick comparison with G1 BC and Applied Ballistics Drag model. Process: Make 2 profiles. 1 uses BC library 1 uses AB Drag model Lock enviromental sensors. Zero wind Here is the table. To break it to you, it seems the G1 profile keeps...

www.snipershide.com

 

[Dthomas3523]

I never even chrono’d my stuff. Used the estimated velocity off either the box or the AB library. Used dsf and kept going.

 

[Near miss]

I never even chrono’d my stuff. Used the estimated velocity off either the box or the AB library. Used dsf and kept going.

How do you overcome ambient temp differences that change the MV?

 

[Dthomas3523]

How do you overcome ambient temp differences that change the MV?

I shoot PRS. Targets are large enough I don’t miss.

I think I missed a total of 15 or less shots in our series this year that goes to 350yds.

If you make the targets small enough that it matters, the top shooters still do fairly well. But the rest of the field gets crushed.

This was in temps from 60-100+

Last match was in the 50/60’s and at distance I was favoring low. If you shoot somewhere like a 30-100 swing, that might be enough to consider.

 

[SkyScrapin]

@Dthomas3523

Are you zero’d at 100y before you adjust DSF?

Have a S&B 3-27 DT2 and I’m working with 39mils of elevation. Need to determine where to zero

 

[Dthomas3523]

@Dthomas3523

Are you zero’d at 100y before you adjust DSF?

Have a S&B 3-27 DT2 and I’m working with 39mils of elevation. Need to determine where to zero

I zero at 30yds. For me, this is the closest to a 100yd centerfire zero. Very little wind interference and everything is dialed up from there.

Once you run the dsf though, you should be able to change your zero in the gun profile (if you were forced to zero at 50 for example) and it will work like normal.

For reference, last match I had to shoot to 350 or so yds and it was around 17 or 18 mils elevation. So, you’d get to about 550yds with 39 mils, give or take.

 

[SkyScrapin]

Once you run the dsf though, you should be able to change your zero in the gun profile (if you were forced to zero at 50 for example) and it will work like normal.

This makes sense, seeing as how you are correcting drops at each yard mark anyways. Zero at 25y to reduce wind affects, then DSF @ 100, 200, 300, 400, and 500 yard.

 

[Dthomas3523]

This makes sense, seeing as how you are correcting drops at each yard mark anyways. Zero at 25y to reduce wind affects, then DSF @ 100, 200, 300, 400, and 500 yard.

Yep. I did it every 50yds. That way I know I’d have the most chances to get 6 points which may need adjustments.

 

[CSchol]

How do you overcome ambient temp differences that change the MV?

In Michigan we shoot a wide range of temperature, I have a few different profiles, say 40-55 degrees, 55-70, 70-85...based on real world crono data at those ambient temperatures.

 

[Near miss]

In Michigan we shoot a wide range of temperature, I have a few different profiles, say 40-55 degrees, 55-70, 70-85...based on real world crono data at those ambient temperatures.

I shoot between 0-95 year around and use the MV table of Kestrel. It helps a lot! Also Strelok MV table was useful but I no longer use the app.

Btw the kestrel MV truing is one way to add new MV input to temperature table, based on drop. I have not used it yet really as I always keep chrono in the car but I intent to try and test does it agree with the chrono. Basically it should, 99%.

 

[SkyScrapin]

Does love me some MV truing based on temp. We shoot in everything from the teens to 100F+. It helps.

For those of you using Center-X, how big of a fluctuation are you seeing per degree?

On a side note, got my Rim-X in and wow, I'm impressed with this sucker. Now if AI could dish out some AICS chassis we'll be in the chips. C'monnnnnn AI.

 

[Near miss]

Does love me some MV truing based on temp. We shoot in everything from the teens to 100F+. It helps.

For those of you using Center-X, how big of a fluctuation are you seeing per degree?

On a side note, got my Rim-X in and wow, I'm impressed with this sucker. Now if AI could dish out some AICS chassis we'll be in the chips. C'monnnnnn AI.

I use Celsius myself, since I am a civilized person. The rate in my testings is somewhere between 0.6m/s to 0.7m/s per degree.
I have not found a good lot of C-X even I have tried a few, but I have some good SK.

My HMR lot of Gamepoint shows 0.55ms/C

To be honest, after checking them, exact value does not matter that much, most important is even some kind of direction towards the right value. An estimate is better than giving it 100% false data.

For example, doing 300m @4C / 39F with room temp chrono data (which is far more precise than box data):
17.66mil
With temp MV correction of 0.71ms/C:
18.35mil

And rimfire ES is huge, so making a careful list is hard. But my guess would be that even 0.5 correction is better than none.

 

[SkyScrapin]

my guess would be that even 0.5 correction is better than none.

What's that in FPS/F - LOL. jk sorta

 

[Near miss]

What's that in FPS/F - LOL. jk sorta

Your temp scale is not linear so I am not sure how to translate SI units to barbarian language.

Here is one example, giving 0.65 ratio in C
39F - 1020fps
70F - 1093fps

So around 70fps per 30F? That is 0.44 ratio now..

You could change your device/app to celsius, set the ratios and then change it back to imperial, I am 100% sure it calculates everything using metrics anyway and just converts the output to imperial for the user.

 

[SkyScrapin]

Your temp scale is not linear so I am not sure how to translate SI units to barbarian language.

Here is one example, giving 0.65 ratio in C
39F - 1020fps
70F - 1093fps

So around 70fps per 30F? That is 0.44 ratio now..

You could change your device/app to celsius, set the ratios and then change it back to imperial, I am 100% sure it calculates everything using metrics anyway and just converts the output to imperial for the user.

Genius! Good call