Co-witnessing question

**pdelcasino** · October 19th, 2010, 05:57 PM

I have a Trijicon TA31DOC optic and YHM iron sights on my AR-15. I'm reading and watching videos about co-witnessing the two.

So as I understand it, I'm supposed to zero the iron sights while looking through the optic, then zero the optic to the front sight. However, my optic is a non-adjustable 4x sight. In order to get the full field of view I have to put it very close to my eye. Since it's magnified, am I correct in assuming I can't zero the iron sights through it?

When I put the optic in a position on the rail where I can see a full field of view, I can't see the front iron sight. When I move the optic forward, I can see the front iron sight, but my field of view through the optic is tiny and shaky.

Is co-witnessing only for non-magnified optics?

**LittleRedToyota** · October 19th, 2010, 06:20 PM

Originally Posted by pdelcasino

Is co-witnessing only for non-magnified optics?

yes.

if you still want to be able to use the irons, you will likely need to mount the magnified optic on some type of riser that lets you see the sight beneath the scope.

**pdelcasino** · October 19th, 2010, 08:27 PM

Thanks for clarifying.

**bac0nfat** · October 19th, 2010, 08:38 PM

Originally Posted by LittleRedToyota

yes.

if you still want to be able to use the irons, you will likely need to mount the magnified optic on some type of riser that lets you see the sight beneath the scope.

Or better yet, have a quick detach scope mount that holds zero. The see- through rings put the scope way to high IMO.

**LittleRedToyota** · October 19th, 2010, 10:21 PM

Originally Posted by bac0nfat

Or better yet, have a quick detach scope mount that holds zero. The see- through rings put the scope way to high IMO.

yes, i would agree that is a better way to go.

**Lycanthrope** · October 19th, 2010, 11:12 PM

Or.....better yet.....

LycanandlearntouseBACthrope

**rwb1500** · October 20th, 2010, 12:31 AM

Originally Posted by Lycanthrope

Or.....better yet.....

LycanandlearntouseBACthrope

Word.

**DaveM55** · October 20th, 2010, 06:18 AM

Co-Witness:

A) "co-witness"- Having the ability to be able to align your Iron Sights or BUIS through your Optics / Red dots (where it locates in the glass it does not matter {middle / bottom 1/3}), leaving your red dot Zeroed.

B) "absolute co-witness"- Sighting in your Optics / Red Dots and then bringing your Iron Sights or BUIS to align with the Red Dots.

**pdelcasino** · October 20th, 2010, 08:14 PM

Originally Posted by Lycanthrope

Or.....better yet.....

LycanandlearntouseBACthrope

That's what I have! Well, mine's black because it obviously looks gnarlier, but essentially the same thing. I didn't even know they keep zero when take them off. It's mounted on a LMT MRP so that may help a little.