I'd say if you can slip a business card between the barrel and the objective, you're probably fine.
Once I decided to mount a scope on my Winchester 52 and get it as low as possible. I got it low all right. The bolt handle wouldn't clear the ocular bell. Had to jockey things around to get it to work.
I'm here to give and receive knowledge, not affirmation or adoration. If you don't like it, mierda dura
. Intellectual honesty is not for fragile egos.