If the scope isn't exactly optically centred, (and most aren't,) when you rotate the scope in the rings, you will get a "smiley." This doesn't mean there's anything wrong. Do a search on "optically centreing your scope."
If you're only an inch out, I don't see how you can't "twiddle the knobs."
If its a .177, zero at 15 yards, then it should be close at 35, so fine tune at 35 yds. If its a .22, make it 30yds.

Gus