I use Strelok Pro, Shooter (paid version), and JBM online.

Shooter and JBM mostly match, Strelok doesn't usually match them.  I play with all of them until I get dope that is reasonably close and repeatable.

Today I had a weird issue.  6.5 Grendel, 12" barrel.  Had targets at 335Y, 425Y, 558Y.

335Y dope called for 2.1 mils up, impact was dead on.

425Y dope called for 3.3 mils up, impact was dead on.

558Y dope called for 5.1 mils, 5.7 was actually required.  Went back and shot 425Y, now 3.8 mils was required.

Barrel was minimally hot. I'd fire five rounds, and then go mess around for a half our or so before repeating.

I'm a little stumped why the 558Y dope is so different, and why 425Y changed mid-stream.  Vortex PST Gen 1, went to Vortex a short time ago for a lube and oil change, and was checked by them.  So for the moment I have no reason to doubt the scope, although I have not done a tall target test.  I did, however, dial during my entire range session, and dope seemed to return to wherever it was I needed it just fine.

Biggest question, does any of the aforementioned software allow for corrections, ie, I tell the ballistic computer that its 335Y dope was good, but that 558Y was off by 0.6mils, and the computer extrapolates that new information to recalculate the BC and then generate a new dope table.

Advice welcome.

How many rounds are on the gun?

The AB app by Brian Litz at Berger bullets should, it does in my kilo 2400 running that program...also applies to MV based off temps...
DSF(Drop Scale Factor is BC)...
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Just shy of 300 rounds.

Thanks, I will take a look at this software vs what I am using now.

That radical of a change in dope would have me re-chronoing the gun.

Usually if there is a discrepancy it is user error or incorrect data input.

If Strelok and Shooter don't agree your inputs don't match. They should agree within an inch of drop even into subsonic distances..

Strelok vs AB Mobile/Shooter (they all output the same), 1200yds look at inches of drop and drift.

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I use Strelok and had some weird things like that happen....The scope is at Leupold right now....The software these days is pretty damn accurate. As long as you enter in the proper data.