To take this down a serious path...

He is correct - it's also something that can happen with the same person too. Try this exercise the next time you are out.

Start standing behind your rifle, with a 5-round magazine in. Lay down prone, take a shot and then stand back up. Repeat this for all 5 shots. You will notice a small shift in POI if you do not get back behind the rifle with a consistent cheek weld. It has to do with the angle you are looking thru the glass (and parallax of course) which can cause the intersection of the cross hairs to float a little.

To demonstrate it the other way lay down with the rifle and shoot another 5-shots without breaking you cheek weld. You should notice that to be a little more consistent.

That's why body position behind the rifle is so important for repeat-ability. It's not just prone, but prone is the easiest way to demonstrate this.

Not to mention that if I get behind the rifle of someone with corrective lenses I will usually be slightly off of that person's zero.

Not inches, but there will be a shift.

not enough to miss a deer

^^Exactly right^^

One thing I teach everyone is to think of the front and back lenses on a scope like irons on a rifle. You must line up front and back lens for there to be any consistency. There has to be edge to edge clearity for 360 degrees, and the scope must be focused. If you get a cheek weld and slightly nod your head, if the reticle moves while doing this you have parralax error and will hurt consistent shooting at any distance.

Dave, Chad, myself and plenty of other THF members acceptible 100 yard zero is about the size of a dime. A long list of things have to be done correctly to ahieve it.

Thanks man.

How muc off are we talking? You say not enough to miss a deer, but are we talking 1 inch or 6 inches at 100yds. First time I've ever heard of this. I know parallax can affect the shot. Serious question: how is then, that with a red dot, the dot can be pretty much anywhere in the lense and you will hit the target. No with that said, I'm not expecting a sub 1 inch group with a 2 3 or 4 moa reticle, so I see a slight point of aim shift due to the reticle covering the target. Maybe I'm too tired to comprehend this right now

Zero a half MOA rifle, hand it to me, my zero may be a couple tenths of a Mil somewhere else, maybe even an elevation and a windage change. Assuming both shooters executed perfectly and the load is very consistent. It doesn't always happen, but it can happen.

I knew it could happen with different shooter due to trigger pull, heart rate, and the such, but never thought about the scope also coming into play with it. Learn something new everyday. And I ain't worried about a few tents of a mil, I measure in MOA

For me, I have to move left about 6 clicks from mechanical zero using AR sights when zeroing. My scoped rifle that my brother sighted was about 5 inches too high.

I personally use the circle method. As the scope moves in circles I try to pull the trigger when it is making the smallest circle. I admit my POI changes constantly but it works in any shooting position

Yup. Sometimes it's a figure eight when I'm unsupported seated, kneeling, and offhand.

i use the drop down method put my sights high and lower them to the target then squeeze the i hit my mark i could never do the circle method no matter haw hard i practiced my dad liked it and tried for month on summer then gave up and shoed me the drop down i like that but i think people should piratic in differs positions if i am on the deg of a find and i can use a tree the just sit down may firing legs i int really do it now with our gaging over so i paretic double kneeprown with and with out bipods you dont alway have that stuff then your in the field and a dead walk up are you can get o you stand your stalking

I start with the raise up, if that fails me then it's to the circle 8. I find that when using the falling method I miss time the shots a lot, as its a more natural position for your eyes to be picking up the upper peripheral than the bottom

Okay, if I use ambidextrous bullets will it give me neutral barrel wear?

just like this one

Well...., met Fonzie today and we got his rifle sighted in. He is a sharp young man, he just hasn't done a lot of shooting. His rifle shot 1.5 MOA which I think is pretty good for a Remington 770 with a package scope.

Thank you again Dwight! Learned allot in that little time.. Also had a great time! I'll get with you after deer season and we'll go slam some hogs!

Cool Beans.