280 AI Ballistics: I need help, I am Confused

Your scope rings may be higher than you think. How low is it at 100 yards?

I agree, double check scope height. You need to know center of bore to center of scope tube. I say this because my scope tube center in low rings with a 30mm tube are sitting 1.7 above bore center. If you have high rings you are likely much higher than 1.8. Just my thoughts. Good luck. Let us know if you figure it out.
 
No scope dials a true .25 per click. We did a square test with a nsx nightforce once that went11"x11" problem is we only dialed 10"x10". We adjusted his speed according, and he has killed 10 plus animals with that scope since. You can also adjust the bullet bc, the manufacturers published number is rarely spot on. Also what direction does your range face? If it's east, then you are experiencing corialis (spin of the earth).
 
Looks like your scope is not quite exactly .25 MOA per click, which is not uncommon. Not sure about your rangefinder, but many ballistics apps have settings where you can adjust this.
This is my thoughts also. Got a little more than .25 moa per click. Would be nice if ballistics app would allow to tweak the click value in the app to the match scope.
 
I have a H S Precision SPL chamber in 280 AI with a Leupold VX6 3-18x44 scope I have worked up a very accurate load 150gr H ELD-X, 59.0gr IMR 4831, Fed. 210M, and Nosler Brass. Velocity has been verified with an Oehler at 3096fps and a LabRadar at 3114fps It's zeroed at 200 yards, dial up 300 yards right on, 400 yards .5MOA high, 500 yards .75MOA high, and 645 yards 1.55MOA high. Dial up was calculated by G7 rangefinder and verified with BulletFlight app., where am I going wrong with my dial up? When I use G7 trajectory verification software it's showing that my muzzle velocity is approx. 200fps faster than my range finder/app.

Can you post a picture of your inputs? I'd almost say hornady undersold their BC's but we know that ain't it 😂😂. The way it's slowly diverging seems like a BC or atmospheric error to me
 
Try .26" instead of 1/4 MOA. Also try using G1 BC. If you are using Hornaday bullets, I'd use the Hornaday 4DOF ballistic program.

Good luck.
 
I would tinker with the scope height input in your ballistic program and see if that changes your dope to match bullet impact.
 
If scope height and click values all check out then I would adjust the velocity to a faster FPS or raise the bc Input value . Sounds like your load is shooting faster then your input value you entered OR your entered bc is off a touch . I'd try bumping the FPS until your required Moa come up matches your actual at the farther yardage then compare it to the closer settings until it matches actual come up to what you are told come up needs to be . If not reset FPS input value back to the initial setting and you can adjust the bc to match too , most of the time it a very small (tweak) to ( validate ) your info and setup . Sometimes your true zero can be off too . Let's say you have it set up to zero at 300 but you looked at your calculations and it says 3" high at 100 , you can be off or pull a shot to throw you off and 1/8 -1/4" or more of ( bad ) information at 100 can really throw you off down range when you try to validate . What ever you choose your 0 range to be , shoot it there to verify that then move out farther
 
Just re read your original post again .....looks like there is enough play between your Oehler and lab radar in FPS ( which did you choose , ? ) I'd start out with playing with the FPS to make it match your actual , I think almost 20fps is enough to cause the difference you are seeing
 
I have a H S Precision SPL chamber in 280 AI with a Leupold VX6 3-18x44 scope I have worked up a very accurate load 150gr H ELD-X, 59.0gr IMR 4831, Fed. 210M, and Nosler Brass. Velocity has been verified with an Oehler at 3096fps and a LabRadar at 3114fps It's zeroed at 200 yards, dial up 300 yards right on, 400 yards .5MOA high, 500 yards .75MOA high, and 645 yards 1.55MOA high. Dial up was calculated by G7 rangefinder and verified with BulletFlight app., where am I going wrong with my dial up? When I use G7 trajectory verification software it's showing that my muzzle velocity is approx. 200fps faster than my range finder/app.
I'd believe what my rifle is telling me versus what software is dictating to me. FWIW I'd make up a range card for the ranges you want to shoot with the corrected come ups from each yard line. What software doesn't account for is variations in brass weight, powder formulas, primer flash, wind effects, etc.
 
My suspicion is the scope is off as the range and MOA increases.
What are your come-ups at those distances?
This is why range testing is important. If your load consistently shoots to those come-ups, make your load/scope specific chart and use that.
 
Just re read your original post again .....looks like there is enough play between your Oehler and lab radar in FPS ( which did you choose , ? ) I'd start out with playing with the FPS to make it match your actual , I think almost 20fps is enough to cause the difference you are seeing

I'd trust the Oehler
 
I'd believe what my rifle is telling me versus what software is dictating to me. FWIW I'd make up a range card for the ranges you want to shoot with the corrected come ups from each yard line. What software doesn't account for is variations in brass weight, powder formulas, primer flash, wind effects, etc.
I too had this problem with a 260 and a leupold. This custom range card was my solution, as I could never get it quite right playing with the inputs.
 
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