I don't have an AR15 but I want to standardize all my mounts at "absolute cowitness" (AC) for ease of maintenance. I have a Trijicon SRS with the fancy quick release that is supposedly AC.
I just bought a Vortex VMX-3T that is AC and also has a spacer for 1/3 cowitness (1/3CW).
I also have a UTG 0.83" riser mount that for the Bushnell TRS-25 is supposedly AC.
The Bushnell TRS-25 and T1 are supposedly the same height.
What I've found that the VMX centre is about 5mm shorter than centre of the T1 on the UTG mount. I have to install the spacer to make it line up. The same with the SRS - it is the same height as the T1 on the UTG mount.
Now after I install the spacer on the VMX, supposedly it is 1/3CW, but how can that be since supposedly the SRS is AC height, and T1 + 0.83" UTG riser mount are also supposedly AC height and they only line up with the VMX with the 1/3CW spacer?
I don't get it!
I just bought a Vortex VMX-3T that is AC and also has a spacer for 1/3 cowitness (1/3CW).
I also have a UTG 0.83" riser mount that for the Bushnell TRS-25 is supposedly AC.
The Bushnell TRS-25 and T1 are supposedly the same height.
What I've found that the VMX centre is about 5mm shorter than centre of the T1 on the UTG mount. I have to install the spacer to make it line up. The same with the SRS - it is the same height as the T1 on the UTG mount.
Now after I install the spacer on the VMX, supposedly it is 1/3CW, but how can that be since supposedly the SRS is AC height, and T1 + 0.83" UTG riser mount are also supposedly AC height and they only line up with the VMX with the 1/3CW spacer?
I don't get it!
