Issues truing my kestrel

[DynamicAccuracy]

I've got the kestrel 5700 sportsman and trying to get it all trued up with my cz455 for NRL22 and some 22lr ELR. SK standard + advertises a .121 g1 bc and I chrono'd it at 1030fps. Kestrel said 2.2mil at 100y but real dope was 2mil. So I added some velocity and a little bit of BC. And it matched real world dope. Went out to 250y and it called for 11.5mil. But real world dope was 9.5mil. Added some more Bc til it was way high at .185 for a g1. Went out to 350y and it called for 15.7mil and it actually took 16.2 mil. I think I'm doing something wrong. I had to put in around 1150fps and .195bc to get it to match my real world dope.

 

[bschneiderheinze]

Probably going to be hard to get a 22 to match up but usually you only change one variable your MV or BC. I adjust BC it seems to work better

 

[Scopes]

Does your scope track true and is your sight height correct? But if it matches your dope all the way out id just use it.

 

[AbbyKatt]

Use the DSF function to true up the DOPE for the .22s. It works great...if the Sportsman does that.

Here's the link...

StackPath

 

[DynamicAccuracy]

Use the DSF function to true up the DOPE for the .22s. It works great...if the Sportsman does that.

Here's the link...

StackPath

I dont believe the sportsman does that

 

[DynamicAccuracy]

Does your scope track true and is your sight height correct? But if it matches your dope all the way out id just use it.

Scope does track true and sight height is correct and if it matched my dope all the way out I wouldnt be having "issues truing my kestrel". I can get it to match one distance but then it's off for other distances.

 

[Kestrel Ballistics]

I dont believe the sportsman does that

Correct the Sportsman (5700) does not have DSF and that is what is needed for most of 22lr flight.

 

[Dthomas3523]

What is your zero range, and what is your environment?

 

[Dthomas3523]

With a 35yd zero, 1118 velocity, and a .132 bc, numbers line up within a tenth of your data.

 

[DynamicAccuracy]

With a 35yd zero, 1118 velocity, and a .132 bc, numbers line up within a tenth of your data.

50y zero

 

[Dthomas3523]

50y zero

And sight height?

 

[POGPride]

With out using a custom curve I have only ever been able to true 22LR to 225 yards.

Not that many people even shoot 22lr that far... but some of the 22lr matches are stretching out quite a bit.

 

[Dthomas3523]

With out using a custom curve I have only ever been able to true 22LR to 225 yards.

Not that many people even shoot 22lr that far... but some of the 22lr matches are stretching out quite a bit.

Do you have a kestrel with the ability to use the DSF function?

I’m able to true to 350 without a custom curve. Haven’t attempted further.

I’m assuming the DSF is almost like making a custom curve though.

 

[POGPride]

Do you have a kestrel with the ability to use the DSF function?

I’m able to true to 350 without a custom curve. Haven’t attempted further.

I’m assuming the DSF is almost like making a custom curve though.

I am sure I do have “DSF” but That is gonna be a new feature for me. I’ll try it.

 

[lte82]

I’m assuming the DSF is almost like making a custom curve though.

DSF bends the theoretical calculated trajectory path based on a single BC to match your bullets actual flight. The custom curve constantly updates the drag coefficient at every step to give you a better calculated trajectory path from the start. DSF works pretty well as long as your atmospherics remain similar. But if you go from 0 DA to 10k ft DA, you'll probably want to verify it.

 

[Dthomas3523]

DSF bends the theoretical calculated trajectory path based on a single BC to match your bullets actual flight. The custom curve constantly updates the drag coefficient at every step to give you a better calculated trajectory path from the start. DSF works pretty well as long as your atmospherics remain similar. But if you go from 0 DA to 10k ft DA, you'll probably want to verify it.

How does DSF work when used in conjunction with custom curve?

 

[lte82]

How does DSF work when used in conjunction with custom curve?

CDM w/ DSF is definitely the way to go especially when shooting purely subsonic. DSF still works the same though, just bends the trajectory path to match. The CDM alone is just going to get you a lot closer when in the subsonic range vs just a G1 or G7 value, so there should be less trajectory truing needed.

The way I understand it, DSF works by essentially bending the trajectory path around specific distances. So you are altering the calculated path based on a specific set of data at one or multiple points, and each data points set of data is unique to that bullet at that specific moment in time (velocity & drag), which is dependent on atmospherics. So the further you get away from the atmospherics you developed your DSF in, the calculated and actual trajectories may diverge. I think the CDM is going to account for a *lot* of that, but I would imagine using only a G7 w/ DSF would not do well if you have big changes in DA.