How important is Eotech/ iron sight co-witness?

[V8toytruck]

Bringing up a month old thread because I've always wondered about this too...

Is the purpose of a co-witness used to back up a failed holosight (HWS) and to use the HWS as a rear sight to align with the front sight to get you on target slightly faster/more accurately?

I thought the whole point of a HWS is so that its super fast on target. I can see how a HWS would be faster to align to the front sight but I figure its even faster (maybe less accurate) just to have the HWS by itself (with no front sight post in the way)

[M. Sage]

Aimpoint/EOtech is for quick target aqcuisition(sp) so that is why you hear 75 yards. I have shot with my Aimpoint to 200 yards with no problem. On a paper target it will cover the whole target but on a man sized target it will do just fine.

Personally I keep my BUIS flipped down when using the red dot. But I can flip it up to co witness if needed should the site fail. I don't think the red dot is designed to be used at more than 1-200 yards but that is my thought. I have an ACOG for anything over 200.

Nah, the EOTech reticle is 1MOA. It's better than the iron sights, and probably better than your rifle and ammo. It's not really meant to be adjusted for windage and elevation in the field from shot to shot, like the rear sight on an AR, but that's the only disadvantage.

[V8toytruck]

I setup my BUIS in order for me to practice a good cheek weld. Some people dont realize that red dots have some parallax so a good weld fixes that.

Have you looked through an Eotech or HWS? If I understand parallax correctly, HWS have very little if any parallax

[M. Sage]

Have you looked through an Eotech or HWS? If I understand parallax correctly, HWS have very little if any parallax

EOTech and Aimpoint seem to have next to none. They have very little at across-the-room distance (where it honestly doesn't matter), and only get better the farther out you shoot. IIRC, Aimpoint claims zero parallax at 50 yards.

After using them in action rifle shoots, I can tell you that at 50 yards and under, cheek weld really doesn't matter with an Aimpoint or EOTech.

[aplinker]

co-witness is a failsafe to a dead battery, damaged electronics, etc. It allows fast transitions in an emergency.

If you're building a close range rifle (which something with an EOTech or Aimpoint generally is), then in critical situations an optic failing can cost lives.

For range use it's not necessary.

Bottom 1/3 is the most useful. It allows you to prop your head slightly up above the FSB and see the dot float unobstructed in the middle of the FOV. With absolute co-witness the FSB will be in the middle of your FOV when the dot's in the middle. However, some guys prefer the absolute cowitness, especially with an Aimpoint, as you can use the circle of the aimpoint as a large ghost ring sight and still make hits.

The Aimpoint Micro series is the way to go - excellent battery life, compact, lightweight, fast and easy. It's also substantially more rugged than the EOTech, which is seeing a schlew of issues.

Bringing up a month old thread because I've always wondered about this too...

Is the purpose of a co-witness used to back up a failed holosight (HWS) and to use the HWS as a rear sight to align with the front sight to get you on target slightly faster/more accurately?

I thought the whole point of a HWS is so that its super fast on target. I can see how a HWS would be faster to align to the front sight but I figure its even faster (maybe less accurate) just to have the HWS by itself (with no front sight post in the way)

[Bad Voodoo]

Maybe someday I'll make a little movie or series of pics to explain... I think the part that people miss is the concept that the dot moves as your cheekweld/eyeline moves.

Wes, I for one, would certainly appreciate something like this. Not being a "rifle guy" I need all the help I can get!

[trinydex]

so with a 1/3 cowitness are you not supposed to have your "normal" cheekweld to the stock? because if you did, then you'd be absolutely cowitnessing with a sort of limited field of view.