Will an EoTech co-witness with A-2 Iron sights if it is mounted directly to a quad rail set up like a YHM or First Samco or will it require a goose neck that attaches to the carry handle and delta ring to boost it up high enough to line up Just didnt want to but a whole bunch of useless stuff if I didnt have to.

VA-Spook

It will co-witness as long as the top rail on the railed handguard is even with the rail on a flat top upper.  I don't own one, but I believe YHM's are even with the flat top.

Ok I have a carry handle A-2 style AR i am not quite getting what you are saying then again it is 2:30 in the morning.

If the mount for the EoTech is mounting the Eotech at the same hieght as the railed YHM tubes or handgaurd then yes it should.  YHM railed handgaurds are the same height as the flat top recievers which will cowitness.  You can even be a little higher and still cowitness, you'll just see a little less of the front sight base.

Bad thing about the YHM handguard is that they move a little though.  At least the bottom one does.  The tops 'pretty' solid.  If I were mounting a Eotech on the handguards I'd use either the Surefire ones, or the floated Daniel Defense or KAC ones.

Anyone have any luck with the First-Samco ones ?

I don't have one, but I would imagine that the Samco handguards would be even more unstable than the YHM as an optic platform.  Not only are they not free-floated (they use the standard delta ring and handguard cap), but they are plastic which would be more prone to flexing.  Between the two, I'd go with YHM.

Quoted: If I were mounting a Eotech on the handguards I'd use either the Surefire ones, or the floated Daniel Defense or KAC ones.

Are the Surefire ones free-floated?

Quoted: Quoted: If I were mounting a Eotech on the handguards I'd use either the Surefire ones, or the floated Daniel Defense or KAC ones. Are the Surefire ones free-floated?

The Surefire M73 is not a free-floating type.

Check out this review of the Surefire M73 with pictures showing how it mounts: tnrdgrnr.com/reviews/M73.htm

Steve.

Quoted: Quoted: If I were mounting a Eotech on the handguards I'd use either the Surefire ones, or the floated Daniel Defense or KAC ones. Are the Surefire ones free-floated?

No but they're pretty rigid, since you tighten down the two allens screws in the front they aren't just held in there by weld spring pressure like YHM handguards or First Samco ones.