Ballistics Trueing

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I also have some Ballistics truing issues.
Strelok is strange for me as well. I use a labradar combined with JBM BC calculator to calculate BC for my slugs/pellets. I've only got 70 yards to test at home.
The 'true' BC i get is ALWAYS different from what the manufacturer states, but I knew that.
What is odd is that is that Strelok seems to always be a little off. If I plug the same numbers in my SIG BDX Rangefinder that uses Applied Ballistics, and range a distance at zero angle, it comes up with a different solution and is typically dead on within the range I calculated BC (~70 yds), if I range something at 100+ yards, the BDX rangefinder is high on it's solution by as much as 1 MOA.
 
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Im going to suggest something that might sound stupid but i had strelock telling me a 33.9 pellet had .5 wind drift @100 in a 2 mph wind and a 34 gr slug drifting 1.5 in same wind. No matter what i changed those stayed the same. Deleted that rifle and put all the same info back in and wala success! Computers get stupid sometimes too
 
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Solo1 said:
Im going to suggest something that might sound stupid but i had strelock telling me a 33.9 pellet had .5 wind drift @100 in a 2 mph wind and a 34 gr slug drifting 1.5 in same wind. No matter what i changed those stayed the same. Deleted that rifle and put all the same info back in and wala success! Computers get stupid sometimes too
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Ha! I'm an IT technician and should of thought of "rebooting". We call that the Microsoft Shuffle - 1st reboot, then work the problem.
 
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Weird happened to me as well. And then I realized...
Change the rifle, close the app and clear the active apps from the screen, open the Strelok again and change the rifle back. This did a trick for me.
I have only two rifles for example but I have many barrels or liners, and swapping 3 scopes on two guns... and I have this many rifle profiles for each barrel - scope configuration. Long story short ... you start changing scope zero and speed and maybe couple more things and for some unknown reason remembers the history.
 
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Ive noticed something similar. I will zero at 50, plug in my muzzle velocity and get my bc. I can shoot out to 300 and its on. But at 150, for some reason im always 3 inches high. Different rifles different projectiles etc. I always seem to be exactly 3 high at 150 and on at every other distance. 50 yards on, 100 yards on, 200 yards on, 300 yards on, 150 yards? 3 inches high. Idk what the deal is but its consistent
 
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GA_LeadHead said:
I also have some Ballistics truing issues.
Strelok is strange for me as well. I use a labradar combined with JBM BC calculator to calculate BC for my slugs/pellets. I've only got 70 yards to test at home.
The 'true' BC i get is ALWAYS different from what the manufacturer states, but I knew that.
What is odd is that is that Strelok seems to always be a little off. If I plug the same numbers in my SIG BDX Rangefinder that uses Applied Ballistics, and range a distance at zero angle, it comes up with a different solution and is typically dead on within the range I calculated BC (~70 yds), if I range something at 100+ yards, the BDX rangefinder is high on it's solution by as much as 1 MOA.
Click to expand...

I think sometimes there is a bug in ballistics apps??

I use SHOOTER app and it has worked well for me(aside from minor tweaking) which seems to be the case with some other apps I've used, but a friend bought a recent SHOOTER app and it is off by quite a bit. We've looked at all the inputs and can't come up with a reason why its that far off. This app isn't well supported anymore since they won't return emails.
When using a different app coupled to his RF his dope is correct.
One other app also is close to his dope.
Also my SHOOTER app is close.

For longer distances with pellets or slugs my S app causes all shots to begin to hit lower and lower as distance increases.
I tried stepped BC's to compensate but it doesn't work well.

OP, some apps have a scope correction feature. You could check to make sure its set to not allow any correction. My friend made that mistake once.
You could also check for a "zero height" and/or a "zero offset" feature to make sure they are both on 0 or without correction.
 
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ccarson2 said:
Ive noticed something similar. I will zero at 50, plug in my muzzle velocity and get my bc. I can shoot out to 300 and its on. But at 150, for some reason im always 3 inches high. Different rifles different projectiles etc. I always seem to be exactly 3 high at 150 and on at every other distance. 50 yards on, 100 yards on, 200 yards on, 300 yards on, 150 yards? 3 inches high. Idk what the deal is but its consistent
Click to expand...
I was getting similar results at times. I didn't do a lot of research into figuring it out yet though. The program will also show a real slow "trued" bc or speed compared to the chrony.
 
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zer0dev said:
I'm pretty stumped here...

I'm shooting my first NRL22 match this weekend, so I went to the range this week to true the gun in Strelok. I've been using the app for a while so I'm familiar with it, however this is the first time I've had access to a real range and the first opportunity to test what it's saying out to any good distance.

The gun is a .22 Impact M3 with the heavy liner, shooting 34gr Javelin / H&N Heavy slugs at ~990 fps. I verified the velocity with two different chronographs (FX wireless and a ProChrono). Strelok is setup with all the correct info on the gun and ammo (0.118 BC @ G1), re-checked the scope height and everything (though this has little impact down range).

I zeroed the gun at 50 yds. Trust but verify... checked the targets with my range finder and good at 50 and 100. According to the app, it's 6.9 MOA from there to 100 yds. Well, it's not. It's 5.5. I went back to check my 50 yd zero and it hadn't moved. I had the chrono at the range and velocities didn't change. Tried both slugs, both sitting at 5.5 MOA at 100 yds.

The Strelok trueing feature wasn't even able to calculate a BC adjustment. The velocity adjustment was 1092 fps!! Like I said, verified 990 with two different chronos. But the new adjustments don't lie. I picked a target at 70 yds after the adjustment, 1.6 MOA, and it was dead on. So I'm confident this will work for the match... but I just don't get it. I also don't know if it will hold out to 150/200. I have access to a 200 yd range and might play around after the match.

I played around with other drag functions in Strelok and nothing really made a difference of more than 1/2 MOA at 100. I picked some random bullet in the list and it did get me to 5.8 MOA, but that's not reliable.

Thoughts? Anyone experienced the same?
Click to expand...
Have you done any sort of tracking tests on your scope to verify a mil or moa is in fact a mil or moa?
 
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@zer0dev I plugged in your numbers to my Strelok Pro app, and let the app load the projectile specs from it's data. It wouldn't let me do the trajectory validation with the bc number either, and jumped the speed up about to where yours was recalculated at as well.

Doing some measured shooting and plugging in numbers to Strelok as an experiment, I just discovered something that I have suspected... Scope height input matters a lot at shorter distance. Scope height is easiest to set up and verify with shooting at short ranges, (if your scope's parallax adjustment goes down to say 10 yards, using a 50 yard zero). I checked my measured long range zero then moved in as close as possible and shot at the bullseye at a measured short distance without moving the scope. The low hit is measurable both on paper and with the FFP scope. This gave an accurate measurable distance on the target to verify and/or tweak the scope height over bore parameter in Strelok.

When messing with the numbers, even a little bit of scope height matters at short range targets. As you know it also mattered but very little at 200 yards, with only with a .250" in hit difference. Interestingly, the closer the scope height to the bore, the slightly more holdover was needed at 200 yards.
 
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Also, not sure how much influence from MOA rails (or adjustable scope rings) meaning if you set the rear higher then the bell.
(For example I had many tweaking to make my scope turret tapes with (old and unsupported) Chairgun Pro from Strelok click values.)
I am suspecting that the adjustable rings (the angle of scope optical centerline in relation to bore) is confusing the numbers in Strelok, and more with FFP scopes.
 
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bigHUN said:
Also, not sure how much influence from MOA rails (or adjustable scope rings) meaning if you set the rear higher then the bell.
(For example I had many tweaking to make my scope turret tapes with (old and unsupported) Chairgun Pro from Strelok click values.)
I am suspecting that the adjustable rings (the angle of scope optical centerline in relation to bore) is confusing the numbers in Strelok, and more with FFP scopes.
Click to expand...
I had this same suspicion as well. With the moa built into some rails and adjustable mounts, there's a lot of difference in scope height end to end. Couple that with where the cross hairs or reticle is printed on a lense in relation to the scope tube, and that becomes a lot of scope height error in the program and in getting the correct dope out of it.
 
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Chairgun uses scope height based on your current zero, i.e. it is not not a constant unless you keep same zero always. Not sure if Strelok might require the same, worth looking into it? Here is an article on it:

airgunaccuracy.wordpress.com

Chairgun and “Scope Height”

I hear a lot of people complaining about the ballistic software Chairgun not being in line with their real world results. But in my field target rifle and scope combo’s it has improved to bei…
airgunaccuracy.wordpress.com airgunaccuracy.wordpress.com

1682061990773.png
1682061990773.png
 
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7Green said:
Have you done any sort of tracking tests on your scope to verify a mil or moa is in fact a mil or moa?
Click to expand...
I have not. It's an Element Titan though, so I trust it. At least, I don't expect it to be off by 1.5 MOA @ 100 yds. That would be a 20% error 😬

To all the comments about scope height... the current value I use is 100% correct. I took two measurements and they are the same. I used partial measurements (1/2 barrel + gap + 1/2 bell), and I did an actual tape measure measurement at the turrets. The middle of the tube to middle of barrel at the turrets is 81mm or 3.19in.

Now the scope height at barrel test is quite interesting. I'll have to try that out today and see what I come up with, and if it makes a difference. I was also wondering how a 30 moa rail might affect the calculations. In fact at 100yds, changing scope height to 2.8in makes it go the other way, and calls for 7.3 MOA. So maybe I won't try it lol.
 
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zer0dev said:
I'm pretty stumped here...

I'm shooting my first NRL22 match this weekend, so I went to the range this week to true the gun in Strelok. I've been using the app for a while so I'm familiar with it, however this is the first time I've had access to a real range and the first opportunity to test what it's saying out to any good distance.

The gun is a .22 Impact M3 with the heavy liner, shooting 34gr Javelin / H&N Heavy slugs at ~990 fps. I verified the velocity with two different chronographs (FX wireless and a ProChrono). Strelok is setup with all the correct info on the gun and ammo (0.118 BC @ G1), re-checked the scope height and everything (though this has little impact down range).

I zeroed the gun at 50 yds. Trust but verify... checked the targets with my range finder and good at 50 and 100. According to the app, it's 6.9 MOA from there to 100 yds. Well, it's not. It's 5.5. I went back to check my 50 yd zero and it hadn't moved. I had the chrono at the range and velocities didn't change. Tried both slugs, both sitting at 5.5 MOA at 100 yds.

The Strelok trueing feature wasn't even able to calculate a BC adjustment. The velocity adjustment was 1092 fps!! Like I said, verified 990 with two different chronos. But the new adjustments don't lie. I picked a target at 70 yds after the adjustment, 1.6 MOA, and it was dead on. So I'm confident this will work for the match... but I just don't get it. I also don't know if it will hold out to 150/200. I have access to a 200 yd range and might play around after the match.

I played around with other drag functions in Strelok and nothing really made a difference of more than 1/2 MOA at 100. I picked some random bullet in the list and it did get me to 5.8 MOA, but that's not reliable.

Thoughts? Anyone experienced the same?
Click to expand...
I just read this I would change the scope height it will get you closer to dead center or bc check this video out. II was shooting my 223 at the range was 380 yards out I was shooting 4” high change my scope height from 2.50 2.10
 
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