Re: My 25yrd site-in, oops!
Depends on the specifics, of course (sight/scope height, etc.) but right about 25-27 yards is where the bullet path first crosses the line of sight for most hunting type set ups. This is referred to as your "near zero," while the point at which we normally zero our rifles for POA/POI (100, 200 yards, whatever), is called the "far zero." If you can resight the rifles to be pretty much point of aim, point of impact at 25-26 yards, you should be very close out at 100-200 yards.
Take a look at a ballistics program if you have one available, and see where the near zero is for your particular set up, and you should be off to a good start.