I went looking at some nice sights today at a local gun store.  They had the sights setup on the fake plastic blue "dummy" rifles so people could play with them.  I looked at the ACOG, AimPoint, and EOTech sights.  I noticed when I was looking through the sights, if I would move my head left to right, while holding the rifle still, the "sight" thingy (red dot, chevron, or what-ever), the "sight" thingy would float and move around.  Is this normal?  How are you supposed to know where the bullet is going to hit if the "sight" is in a different spot each time you pick up the rifle?
How are you ever supposed to really zero your sights if this happons?

Are they any sights that don't float?


Thanks guys

Yes normal!

For the Aimpoint and Eotech, there is almost no parallax, so if the dot is on the target when you pull the trigger, you are going to hit it. With any optic that has any magnification it is critical that you always have the same sight picture every time you put the rifle on target. To get the same sight picture, you must always put your cheek on the stock in the same place, this is why some people put their nose to the charging handle on an AR15.

Am I crazy, or is this the way sights are supposed to be?  

You're crazy

It's hard to explain, but basically wherever the dot is, the bullet will hit. It's a holographic image (in the eotech, aimpoint is sort of the same) Anyways, it only appears to move, thats what is so nice about these sights, nothing to line up. dot on target- shoot.

eotech has paralax im pretty sure. well to quantify that statement.. every eotech i have used had paralax up to about 20 feet or so. if i set the sight on something steady like a table or desk and looked through it at something too close the reticle would move around on the target which it shouldnt if the sight is sitting on something steady and you are movng your head. when you do this on something far enough out it doesnt do it.

Both EO techs and Aimpoints have parrallax at close range and that's why the dots appear to float.  They move slightly but this amounts to approximately 2inches under the no parrallax distance in most circumstances.  It is negligeable.  Eo's under 25yds, Aimpoints inside 50.  


Buy an EO - Use it and realize it barely exists.  With the Aimpoints it is noticeable but still close to unimportant (as long as you zero your aimpoint at 50-100yds it won't be an issue.  Sighting at 25meters can cause poor zero's at 250+meters.  I say 250 as that is where rounds begin to occaisionally miss E-types when I zero an Aimpoint at the Army 25meter range.  That's another reason I prefer an EO tech- I can get a good 300m zero from the rediculous Army zero range of 25meters.  

Quoted: ...With any optic that has any magnification it is critical that you always have the same sight picture every time you put the rifle on target. To get the same sight picture, you must always put your cheek on the stock in the same place, this is why some people put their nose to the charging handle on an AR15.

This is not exactly true.

If the scope (optic) has been focussed on the target there will be no parallax.  As with an Aimpoint, the reticle will appear to move relative to the scope housing but relaticve to the image of the object the reticle will not move (rather, the reticle and target move together).  

You can check for the proper focusing of your optic by moving your head around and observing the absence of paralax.  

ALL of the red dot type of optics will have a small amount of parallax under 25M, beyond that range you can expect a parallax error that is roughly 3/4 the size of the dot.

I fixed my statement for thoise who think the small amount of parallax a red dot optic has is a critical point for the guestion asked.

michealj,

I wasnt trying to attack your statement, but it is the small amount of parallax error in the optics that is causing the dot to "float" at close ranges, so yes it is a critical point for the question asked.