Re: anyone using shooter app
It probably would not give you that much variation, but with the iSnipe app will automatically fill in environmental conditions based on your location. If they are way different than what you made your proven charts at, that may have something to do with it. Again, probably not, but another option to look into.
I have also been guilty of accidentally outputting a chart after messing around with the angle feature, and forgetting to re-zero it. Whoops.