Aimpoint QRP Mount On Flattop With Fixed Front Post

[.45's and .38's]

So I Just picked up a new AR. It is a Standard Flattop 16" M4 profile with a F Marked Front sight post. I just got a great deal on a Aimpoint QRP mount off the forum. From what I have learned there are 2 pieces to this QRP mount you may or may not need. The Spacer Ring. If you google it, it is "12227 Spacer ring".

So my question is, If I use this QRP with a new optic I got...Just as the mount is now on my Upper receiver, Will I get any co witness?
I dont care if It is 1/3 Lower or absolute, I Just want it to work with my front sight post that I do not want to remove.

QRP is Model 18884
Spacer in Question is Model 12227 (I do not have the Spacer ring)

More Info
Rear Sight Is Midwest Industries ERS BUIS
Front Sight is a Fixed F marked Post
Red Dot will be the Primary Arms 30mm Classic

[.45's and .38's]

nobody?

[buckar15]

It should absolute co-witness.

[.45's and .38's]

You are correct

I ended up not needing the spacer mount after all!

[WaldoOneFive]

Yes, using the mount without the spacer gives you an absolute co-witness, whereas if you install the spacer, this will give you a lower 1/3 co-witness. Some folks prefer the absolute co witness, and others the lower 1/3.

[Eric]

Yes, the spacer is supposed to be used with the standard M4 type flattop configuration. Without it, the optic will sit too low. With the spacer (shown installed in the photo) you end with with something between an absolute co-witness and a lower third.

[.45's and .38's]

Interesting. That is a different spacer than I was thinking.

What is the model # on that?

[WaldoOneFive]

Interesting. That is a different spacer than I was thinking.

What is the model # on that?

Yes, the one picture above posted b "Eric" is a different mount/spacer combo... that is the QRP2 mount.. Your original QRP mount uses that "12227 Spacer ring" and works as I described in my previous post.

[.45's and .38's]

Ok so the QRP 2 is a whole different mount that uses a different 30mm ring then the one I have? I have model 18884

I know 12227 for my 18884 put it at a lower 1/3 co witness
Will my 18884 go on the QRP 2 to raise it up for 1/3 also?

just making sure I got this info 100%

[Eric]

Obviously I should have been more attentive to the details in the original post. The original QRP (discontinued) does use the spacer ring for the lower third configuration. The one I have shown is the current QRP2 mount with an Aimpoint PRO. The spacers are not interchangeable. The PRO comes from Aimpoint with the spacer already installed. Both mounts will accommodate the 30mm tube.