I'm shooting 6BR 109 eldms @ 2750. I range the targets using my sig kilo 3K and input the data in my kestrel 5700. I'm consistently impacting well above targets past 700 yards. Any suggestions on how to troubleshoot this?
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PRS Talk Impacting high past 700 yards???
- Thread starter Fullbore1912
- Start date
Need to true your data. Spray a water mark line across your targets(horizontal). Take the data your kestrel is giving you as a starting point. Keep dialing down in your case till you are hitting on or very near the line. Do this for each distance that you have (700, 800, 900, 1000, etc) and right down what your actual dope is at those distances and then true your BC in the kestrel. There may be a custom curve for those bullets in the kestrel.
What Jet said, if you are using the AB curve just true up your muzzle velocity to make the Kestrel output true up to the actual dope needed to line up to watermark. If you are still high beyond 700 after truing MV then play with the BC by changing out of the AB curve.
I have found just truing MV works perfectly when using AB curve
I have found just truing MV works perfectly when using AB curve
AB I think says you True MV until you reach Mach 1.2 or 1.1 (transonic), and then you true BC. So at 700 yards nearly everything for PRS is going to be MV. Most BR cartridges are transonic at like 1100 (or whatever the math says).
Double check your wind directions, since wind direction has an effect on elevation.
I thought my kestrel was reading wind direction with a 6mph wind this weekend and shot high for a bit before seeing that the kestrel still had a 12:00 wind instead of 4:30 (the actual direction). The difference in dope at ~500 was .2 high with the 12:00, and I ended up sending it over the top a lot.
I thought my kestrel was reading wind direction with a 6mph wind this weekend and shot high for a bit before seeing that the kestrel still had a 12:00 wind instead of 4:30 (the actual direction). The difference in dope at ~500 was .2 high with the 12:00, and I ended up sending it over the top a lot.
The most common cause of this issue is one or more incorrect inputs. Some of the most common are units being set to meters but range is in yards, incorrect scope heigh over bore in gun setup, and wind direction set to manual rather than with direction of fire.
One other thing to validate is your fundamentals. I personally have observed myself missing high at long range, specifically using a bipod and rear bag, and tracked it down to insufficient shoulder connection combined with minimal rear bag pressure; under recoil, the poorly supported buttstock would drop, raising the muzzle and the POI.
Here's a little true story that may be relevant. I was in a Frank/Marc clinic at Mifflin...oh, maybe 3 years ago. Frank asked if he could shoot my rifle...of course I said yes.
He hammered the 600 yard target with my dope.
I jump down on the rifle...same dope...and I'm shooting high and missing the target. Frank was spotting but even I could see the splash on the berm behind the target.
Frank and Marc (really both...I got double teamed! haha) said I was letting my rear bag lean backwards. That is, it was not completely upright allowing the bag to hinge down under recoil and hence shoot high.
I said "no, really?" They both replied in unison...."yes, we saw you, don't argue". Me..."ah, ok" lol
I kept the bag upright and slammed that target repeatedly. Small fundamental error showing up at distance.
Might not be the OPs issue but its a lesson I haven't forgotten and may be of use.
He hammered the 600 yard target with my dope.
I jump down on the rifle...same dope...and I'm shooting high and missing the target. Frank was spotting but even I could see the splash on the berm behind the target.
Frank and Marc (really both...I got double teamed! haha) said I was letting my rear bag lean backwards. That is, it was not completely upright allowing the bag to hinge down under recoil and hence shoot high.
I said "no, really?" They both replied in unison...."yes, we saw you, don't argue". Me..."ah, ok" lol
I kept the bag upright and slammed that target repeatedly. Small fundamental error showing up at distance.
Might not be the OPs issue but its a lesson I haven't forgotten and may be of use.
What were the weather conditions?
Remember, your kestrel automatically calculates AJ. This means winds from the left push down on an RH twist barrel, while winds from the right push up. Ensure your azimuth and wind directions are correct. Also, note berms/obstacles underneath your line of fire. Depending on wind direction, they can push your impact high. Finally, remember, Sun's up, Gun's up. When you have a lot of mirage, the target will appear higher.
Remember, your kestrel automatically calculates AJ. This means winds from the left push down on an RH twist barrel, while winds from the right push up. Ensure your azimuth and wind directions are correct. Also, note berms/obstacles underneath your line of fire. Depending on wind direction, they can push your impact high. Finally, remember, Sun's up, Gun's up. When you have a lot of mirage, the target will appear higher.
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What scope are you running? If you haven't run a tall target test to confirm the accuracy of your turrets, you should do this before anything else.
Change your wind to zero mph and see if that lines up (aka aerodynamic jump turned off).
I am not a fan of truing muzzle velocity ad you are taking a known variable and changing it. Name of the game is have as many known variables as possible to distil down to the most reliable solution.
If you are using AB custom curves then Something is wrong with your other inputs. I would bet money on this. You could also switch to g7 and true the BC. Hornady bullets have a very high bc variance compared to berger and Sierra, which will add noise to the system.
If you are using AB custom curves then Something is wrong with your other inputs. I would bet money on this. You could also switch to g7 and true the BC. Hornady bullets have a very high bc variance compared to berger and Sierra, which will add noise to the system.
Is there videos that show how to true bc on the kestrel. The drop scale factor on my leica ab works well but nothing changes when I try to adjust things in the kestrel device . The lady in the kestrel video shows it but her data lines up perfectly so she doesn’t show you how to adjust anything . Are you only able to adjust bc if your using g7 and not custom curves?
It's pretty easy. You want to shoot as far as you can, as close to transonic as possible. For a 6.5cm 1.1-1.2k at sea level with most high bc bullets Is pretty good. If the furthest you shoot is say 800, then true for 800.
Start with a Good estimated BC. Either what's on the box, the AB library or in Hornady 4dof. If your shots are low, then lower the BC until you hit water line. If your shots are high, then raise the BC until it matches. All you are doing is trying to find a constant that works in the equation, which is what a ballistic app is. You don't have to be exact, within a point or two is fine.
For example, 143 Norma golden target is listed at .321. AB PDMs are around 302. When I trued it, I got .305 and that's what everyone I know uses as well.
If you are using custom curves you cannot change the bc. That's why doing mv is even crazier as you now have 2 fucked up variables.
If for some reason the custom curve does not match ( every one I have seen has been within a tenth out to transonic) or there is no custom curves, then use g7.
I still argue if your custom curve is not matching something with your inputs is wrong. I would wipe everything clean, start fresh and remeasure everything.
If for some reason the custom curve does not match ( every one I have seen has been within a tenth out to transonic) or there is no custom curves, then use g7.
I still argue if your custom curve is not matching something with your inputs is wrong. I would wipe everything clean, start fresh and remeasure everything.
This is what I was having an issue with. Thanks
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