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6/30/2008 7:20:27 PM EDT
Does anyone know of a rail mount, fixed style, rear BUIS that will give me a lower 1/3 cowitness behind an Eotech 512 without a riser being used for the optic?
6/30/2008 7:47:02 PM EDT
[#1]
It doesn't work that way. The height of the iron sights is set by the front and rear sights together. Where the co-witness on an optic is determined by the height of the optic, nothing else.

If you want a lower 1/3 co-witness w/an Eotech, get the Larue mount.

BSW
6/30/2008 7:56:17 PM EDT
[#2]
Is the Larue fixed buis any lower than standard?
6/30/2008 8:21:08 PM EDT
[#3]
No.

If you had a lower rear BUIS you would build in a fixed elevation change. You would not be able to zero the rifle.  Long range scope bases do work that way, they are ramp shaped and cause a fixed elevation change when scopes don't have enough elevation adjustment.

BSW
6/30/2008 8:26:35 PM EDT
[#4]
Understood.
What prompted the question was seeing some setups using the fixed Larue buis behind Eotechs. It looked as though the buis would be distracting while trying to use the optic at the same time.
7/2/2008 8:17:52 AM EDT
[#5]
I have run both Absolute and 1/3 cowitnesses. People make a big deal about the rear sight being in the way and cluttering up what you can see.

If you are properly zoned in on your target and the dot, you won't even really see the rear sight. I always ignored it and it's not an issue to me. I felt I was faster with the absoute co-witness but I am still wringing out the LaRue I now have that gives me a 1/3, so I havn't made a decision yet which I like better.

Try it with the EoTech mounted straight to the receiver rail with the LaRue rear sight. See if you like it. If not, then you can upgrade with something like the LaRue EoTech mount to raise it up and you're not out any money that way if you don't like something.
7/3/2008 7:23:13 AM EDT
[#6]
Thanks. I'm going to give the fixed buis from Larue a try!
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