I have an M1A with a Leupold 6x18 scope on a Bassett low mount. I am considering getting an additional mount with a holographic site so that I can do some bang, bang, bang, instead of just bang. The iron sights are great, but the eyes are not. I have read that the Bassett keeps the zero pretty close when removed and replaced. True? I want to switch back and forth the sight arrangement. My other scopes are on bolt actions and not removed for 35+ years so I am skeptical. Please advise.