Any Sig 2400 ABS Experts?

[Triple BB]

I'm shooting a 338 Edge that is shooting 1/2 MOA accuracy or better at closer distances. Problem is, my shots get progressively lower the further out I go. 100 -300 yards, dead on. 400 yds an 1" low. 600 yds 4" low. 1271 yds 26" low.

My muzzle velocity is 2790 shooting a 300 grain Berger Elite Hunter with 90.5 grains H1000 and ADG brass. My ES is under 20 fps using a Magneto Speed. I'm at a loss at what is going on. Was looking at doing a ballistic calibration but the first range in the ABS is 1701-1892 yards and the second is >2748. Since I apparently can't calibrate for a specific yardage, there's know way to generate a drop scale factor with this bullet since I have no way of accurately measuring drop at 1800 yds or over 2748 yds.

Any suggestions on a fix? Is it an improper velocity issue? Anyone with similar issues and the ABS?

 

[jimbires]

when you plug in the velocity , you need to be in the field under the conditions the velocity was recorded at . the sig has a weather station built in .

be sure your zero , is zero . being an inch high at 100 yards , is not a 100 yard zero .

does the scope move precisely per click .


when I first set up mine I made a couple mistakes . I put the velocity in while I was in my a/c house , instead of in the field under the conditions I shot at . I also didn't calibrate the compass .