Here are some photos of a TA31 mounted on a GG&G ACOG mount and installed on an M4gery sporting a KAC RAS II and KAC 300m BUIS. You will see in the photos that I tried it with the lever to the left and to the right. Both options fit fine but there is only one location into which it fits. Both the ACOG mounting screws and the crossbar are offset from the center so even though the mount sits a little further forward with the lever on one side vs the other, the ACOG itself seems to end up in about the same position. The position of the ACOG is a little more toward the buttstock than with the factory TA51 mount. This helped me with a little more comfortable eye relief.

The mount seems very well made and sturdy.The lever design makes it really easy and fast to open the lever, even with a gloved hand. I am very pleased with the fit and ergonomics. I am not sure if I like the right or left side lever location.  I'm left-handed and am favoring the right side but time will tell.

I would like to thank Brett at Primary Arms, LLC, for his great service and much appreciated assistance in finding a mount that fit my weapon and my preferences.

Right side lever:








Left side lever: