Having trouble with ballistic apps

volunteerbee

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Ok guys and gals! I'm fairly new at this. I've been shooting long range for almost a year now and I've started playing around with the 6.5x284 Norma. I have a factory rifle. Savage 111 LRH. I'm currently shooting factory loads but plan on reloading it in the near future. I'm shooting HSM loaded with 140gr Berger hunting VLD's. All the ballistic apps I've tried are off on the call for 500-650 yds and 800-900 yds. All my rifle information is entered correctly and I chronographed the ammo so I know it's all correct. The apps call for 8.5-9 MOA at 550yds but it's actually 6.75MOA. Just an example. It's also good out to 1275yds. There's just a small window where it's off. Any ideas or help would be greatly appreciated. Thanks
 
In these situations it's always going to be the information is messed up somehow.

However before the masses come down, you might as well add what ballistic solver you are using and what kind of chrono, how you are acquiring your ranges, which drag model you are using, which doesn't matter quite yet but it might later, and if you trued anything yet.
 
Thanks for the reply. I'm using the Hornady 4DOF app as it seems to be the closest one overall to matching my flight trajectory. I'm using the native drag model for the 140gr Berger VLD hunting bullet in g7. I'm getting my ranges from my Nikon 4K. I'm getting the weather readings in real time including altitude. Chronograph is a magnotech 5 shot average. I'm not sure I know exactly sure I know what your asking for when you ask about truing anything. If your referring to the action then no I haven't. Only thing extra that was done was I did lap the rings. I haven't completely ruled out the optics but I really don't think that's an issue. I'm running a crimson trace series 2 6x24x56. I'm just at a loss as to how it can be correct at 1200 yds and be that bad off at 550.
 
What does real time mean? A kestrel? Because that's about the only way the 4dof works. A kestrel or something else that can calculate DA.

I'm not talking about your gun. Ballistic truing is a ballistic data thing. It's a method of aligning the numbers to mathematically be correct.
Trueing is a form of tweaking your numbers, particularly your mv and your bc to match the reality of your shot. The further out you go before you run out of hit probability there's always a level of truing. 4dof does things differently. muzzle velocity calibration might just be tweaking the number, then muzzle velocity temp calibration. You don't need to do the powder stability for factory ammo, actually most dudes I know are getting better results with 0. You probably need to tweak your mv 1-20 fps. There is axial form factor, i'd do that around 700-800 yards if you can after you fix the 200-500 yard problem.

I'm not sold on the whole zero angle thing, I'm sure someone on here has an opinion on it but I know if you use it and miscalculate it, it will throw your solution.

Then lastly subsonic range truing. That is for beyond transonic, you need to line up your dope in the 200-600 yard range first. You can use the axial form factor or bc to tweak.

Basically your 200-600 should be good just based on mv. Your 1000 yard and beyond should need refining in other ways.
 
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dfanonymous, thanks for the help. I'm going to go back and redo everything and run another 5 shot mv to double check everything. One thing that may be messing me up is I'm not using a kestrel but I'm getting ready to order the one that links to the 4dof app. I'm currently getting my readings from my phone. I'll update in a few days when I get the kestrel in and run everything again.
 
Ok guys and gals! I'm fairly new at this. I've been shooting long range for almost a year now and I've started playing around with the 6.5x284 Norma. I have a factory rifle. Savage 111 LRH. I'm currently shooting factory loads but plan on reloading it in the near future. I'm shooting HSM loaded with 140gr Berger hunting VLD's. All the ballistic apps I've tried are off on the call for 500-650 yds and 800-900 yds. All my rifle information is entered correctly and I chronographed the ammo so I know it's all correct. The apps call for 8.5-9 MOA at 550yds but it's actually 6.75MOA. Just an example. It's also good out to 1275yds. There's just a small window where it's off. Any ideas or help would be greatly appreciated. Thanks
F345A42C-6217-43F9-B61B-AFF70CBA6B32.jpeg
 
I also run a 65 284 Norma custom built rifle and shoot that exact bullet right now I am at 52.5 grains of reloader 23 @ 2985 fps this is a picture of my drop chart out to 1250 yards everything has been Trued to within one click
 
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Here's an example of the difference of the weather station vs where you're at just in pressure.
 

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Have you shot this on more than one occasion to verify or was it a one and done thing?
May sound silly but what scope are you using and have you verified it's adjustments are true and repeatable? If not then I wouldn't expect everything to line up, because it might not. I've seen scopes adjustments have dead spots (weak/strong adjust). Ive also had a rather expensive scope that's adjustments were 10% off...that's horrible, but crap happens.
 
Honestly, I would do 2 things. 1st, I would run a tall target test to see how your scope was tracking. I once had a scope that at a certain place in the rotation of the turret, it would hang up, and them free itself as I rotated. You can check thos via the tall target test, or shoot your 550 yard target using hold over instead of dialing. Shoot 100, 550, and 1200 all using hold over and see if you have the same anomaly. 2nd, I would recertify that your target distances are correct. I once had an issue where my ra.ge finder was getting a funky read and the way the targets were aligned, and sized, I was actually shooting g at a 700 yard steel, when I thought it was 600.....really had me messed up.
 
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