Gene - We tried some back a waile ago and I didn't see any change. there are some many objects out there for reference and just experience gets the scope level.
Glancing away from a target in a battle area to insure scope level begs for the target to be gone when you glance back.
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Hold Hard guys
Rick B.
Knowledge is knowing a tomato is a fruit.
Wisdom is knowing it is great on a hamburger but not so great sticking one up your ass.
Author - Richard.
Experience is what you get right after you need it.
Author unknown.