I'm not getting what you are asking either? My hunch is you need to sight in the Red Dot. And/or back your eye away from the scope a bit. And/or your expectations of accuracy are unlikely to be fulfilled anyway. Red Dot isn't for accuracy.
You shouldn't have much parallax, the exception being if you are way to close to the sight. Red Dots are designed to have very little parallax.
Accuracy and a 3 Mil Red Dot is kind of an oxymoron. 1 Mil is like three inches/ 3 MOA (I think it's 3.3 inches ?) at a hundred yards. A 3 Mil red dot and the dot covers almost ten inches at a hundred yards.
You throw the rifle up there, put the Red Dot on center of mass and pull the trigger. The bullet should hit some place in that ten inch circle at a hundred yards.
My Red Dot is like twenty years old ( on a Mini 14), the way I sighted mine in was on an old style 10 ring target (500 meter rifle target) at a hundred yards. I'd center the Red Dot inside an outer ring and see where my bullet struck the target. Adjust the sight until the bullet is near center or actually 2 inches high at a hundred yards, which is just my preference. My Mini shoots 3 MOA anyway on a good day.
You can do just about the same if you have a rifle vise, center the iron sights on a 10 ring target then move the Red Dot as close to center as you can guesstimate.
Found this.
http://smith-wessonforum.com/smith-w...-trs-25-a.html