280 AI Ballistics: I need help, I am Confused

[arch408]

You might need Strelok Pro which can calculate dial up at any power. Or I could be totally out to lunch with a terrible cerebral anal insertion.

 

[jpope02]

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 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.

Verify your altitude and station pressure.

 

[santee116]

Good article and video by Bryan Litz on scope calibration. As he states, many scopes have "over travel" or "under travel" with regards to real world click values. They can be calibrated with a correction value on most ballistic apps.

Calibrate Your Clicks with Tall Target Test « Daily Bulletin

Have you recently purchased a new scope? Then you should verify the actual click value of the turrets before you use the optic in competition (or on a long-range hunt). While a scope may have listed click values of 1/4-MOA, 1/8-MOA or 0.1 Mils, the reality may be slightly different.

bulletin.accurateshooter.com

 

[SSgt G Cody]

Rodney,

 

[SSgt G Cody]

Rodney, I'm a bit confused: You say your scope is zeroed at 200 yds, yet flat (no drop) at 300 yds, and gains (not drops) at 400 and 500 yds. That's impossible. It sounds almost as if you're looking at a mirror image, or reversing scope/target drops. Your description of your rifle sounds like it should be shooting great! Get someone at the range who's very experienced to double-check your measurements. It should be a simple fix. Puzzles do sometimes exist, but at long distance, it's hard to help you much. I have a .284 myself, similar to yours, and it's a real tack driver. Hope you get yours squared away!

 

[SSgt G Cody]

Rodney, After re-reading your original text, I now see what you were asking. Sounds as if your scope needs to be tweaked a bit to more closely match your trajectory. Is it perhaps still set to a 160 gr. bullet, or a differently shaped bullet? Still sounds pretty simple.