My rear flip sight came and the threaded nut is a little too wide/long. The corner of the block hits in the radius of the groove and makes it tilt forward. I never thought of checking something like this but it could have saved me a shiny spot on my upper.
Also my troy mrf-c is not flat with my A3 upper. Its definitely angled upward and I've tried forcing it down while locking it in place.......all to no avail.

Troy Rear SIGHT

Anyone have similar problems? I will contact the vendor tuesday and see if things can't be made right.

Looks like the base of the sight is in a 10-15 degree nose-dive.

I have installed one mrf-c and it went on great. Have another waiting for my new upper and I expect the same. How did you install it? Did you use a detachable carry handle etc to make sure the rail & flattop were level as you tightened the bolts?

The threaded block on the sight is indeed nosediving. On the mrf-c I used a straightedge to make sure it was aligned. It stayed straight with the A3 until the final few turns of tightening and then it kicked upward. Granted its 2 or 3 degrees but do I really want to crank the elevation down on my eotech if mounted out there? Also leery of mounting my eotech so that its resting on both pieces since they are not on the same plane. I will have to wait until Tuesday to find out.

A trick I got from here was to set the two pieces up next to each other and then bolt the carry handle to it so one clamp is on the forearm and one is on the upper. That holds them together nice and level as you tighten the rail down.