Down Under Hunter
Well-Known Member
The ongoing mystery continues with learning how to use exbal and my new rifle.
Today I went out and fired a cold bore shot at 1100 M. This was with 32.25 up. Exbal said 34.25 up.
Conditions were
89 temp
RH 42 %
FPS entered was 2830
I believe that my other data may be inaccurate as I had an Alt reading that was vastly differerent to the last time I fired from the same spot.
I have hopefully corrected this by calibrating the kestrel with a ALT and BP reading from the local airport weather station when I got home.
Anyway as the temp rose and conditions worsten I decided to just fire at a close target of 415 M.
Entered the range and a BP of 29.66 and dialed the 7 up and sailed at least 2 moa over the top. At this stage I did not think there was much up draft happening as the wind was 10 oclock 3-4mph.
This shot is down hill 20 degrees for 200 then rises about the same angle to the target.
I used cosine .99.
After the forth shot my elevation correction was back to 4 moa up and I still went over the top of the plate. Wind had swung to 7 0clock following and around 6 mph. Then I gave up because I felt either the high temps where at work again or something very fundamental is wrong in my settings To hit the plate I would of had to be less than half the ups exbal gave me ? Over a distance of only 415 this does not seem possible to me ?
I am going to check the 100 meter zero again, and short of the gun being way high at that range I am lost ?
Can anyone suggest what else I have not thought of that could cause the PDA and actual ups needed being so different ? I understand that the BC given to the 300 SMK by exbal is very accurate. The way I am going, the PDA is worthless when it is so far out.
What factors would you need for a 338 edge doing 2830 to only need less that 4 moa up over 415 m. I just dont see weather conditions being that big an influence over that distance ?
I have given the scope height 2 " above the bore which I think is reasonably accurate.
Hunting season starts in a few weeks and now I am tearing my hair out !
If I find this week that the 100 zero is dead on, where do I go ?
Signed....Frustrated..Cheers DUH
Today I went out and fired a cold bore shot at 1100 M. This was with 32.25 up. Exbal said 34.25 up.
Conditions were
89 temp
RH 42 %
FPS entered was 2830
I believe that my other data may be inaccurate as I had an Alt reading that was vastly differerent to the last time I fired from the same spot.
I have hopefully corrected this by calibrating the kestrel with a ALT and BP reading from the local airport weather station when I got home.
Anyway as the temp rose and conditions worsten I decided to just fire at a close target of 415 M.
Entered the range and a BP of 29.66 and dialed the 7 up and sailed at least 2 moa over the top. At this stage I did not think there was much up draft happening as the wind was 10 oclock 3-4mph.
This shot is down hill 20 degrees for 200 then rises about the same angle to the target.
I used cosine .99.
After the forth shot my elevation correction was back to 4 moa up and I still went over the top of the plate. Wind had swung to 7 0clock following and around 6 mph. Then I gave up because I felt either the high temps where at work again or something very fundamental is wrong in my settings To hit the plate I would of had to be less than half the ups exbal gave me ? Over a distance of only 415 this does not seem possible to me ?
I am going to check the 100 meter zero again, and short of the gun being way high at that range I am lost ?
Can anyone suggest what else I have not thought of that could cause the PDA and actual ups needed being so different ? I understand that the BC given to the 300 SMK by exbal is very accurate. The way I am going, the PDA is worthless when it is so far out.
What factors would you need for a 338 edge doing 2830 to only need less that 4 moa up over 415 m. I just dont see weather conditions being that big an influence over that distance ?
I have given the scope height 2 " above the bore which I think is reasonably accurate.
Hunting season starts in a few weeks and now I am tearing my hair out !
If I find this week that the 100 zero is dead on, where do I go ?
Signed....Frustrated..Cheers DUH
