adjusting dope

[Tac]

I went out yesterday to verify my gun zero and practice shooting long range with my isnipe program.

My zero is at 200 yards and average speed of reloads is 2832 shooting barnes 265 lrx .338 lapua.

put this into the i snipe and look for output and it call for 2.34mil adjustment and i shoot high back of .4 mil and it hits.

what would be the reccomended way to correct the program?

i also shot at 400 yards and program called for 1.1 mil and actual shooting was .8 mil.

[Tac]

i was shooting at 575 yards for .4 mil adjustment

[STOMP442]

Check your scope height and use the correct G7 BC drag function. Also make sure that your altitude and pressure are correct.

[firstcoueswas80]

Scope height is a big issue. What we're you using to determine wind speed?

[Tac]

the scope height was 2.0 the wind and pressure was set from the local wheather station. shooting due north and wind approx 7mph from the east but gusting.

i was more interested in high adjustment high enough to cause a miss i beilieve.

i had a 5 degree angle to target that was also accounted for

[DesertBull]

Most likely an adjustment to velocity. Try trajectory validation calculator. I'm not sure if iSnipe has it but the Vortex website has one.

 

Is the BC number that iSnipe uses for that bullet from Barnes or Litz?

[Tac]

I put in the BC from Barnes

I will adjust velocity seems to be logical answer

[couesman77]

your velocity is faster I use shooter and it has a velocity calculator and everything is good but I do it at 1000 yards

[goatsie]

Did you chrono? Or are these book velocities?

[lancetkenyon]

You have to take known drops at known yardages to true your velocity. Make sure everything else is 100% correct, atmospheric conditions, altitude, temp, humidity, BC of bullet from LITZ (Not from Barnes), scope height, etc.

 

I try to use at least 5 distances and actual drops to true my velocity. And not just hitting an 8-12" plate. You need to be center hits, from 500 and out.