I saved my pennies and got myself a rear sight (the one I was using was a loaner). I chose a Centra that was intended to attach directly to the rail on top of my AR, which it did. Here is a picture of it attached to my AR:
I took it with me to a high power practice at Minneapolis rifle club but I didn’t arrive as early as I had intended; which turned out to be a good thing because I figured out a very simple way to transfer the zero from the loaner sight to the new one.
I attached the new sight on the rail in front of the loaner and with the loaner set at my 300yd zero, adjusted the new sight until I had its aperture lined up between the loaner and the front sight rings. Then I removed the loaner and slid the new one back into position. It worked well because my first shot was in the 9 ring.
After sighters we shot a couple of rapid fire strings (in both strings the last round jammed, I think my bullets are seated slightly too long), I scored two 98/100. Then we shot a 20 round slow fire string. Below is my scorecard (which I discover is not quite the right one for 300yd slow fire, despite what it says).
(I didn’t record the elevation as I hadn’t adjusted the scale plate at that point).
Pretty nice I thought: although I have to ask what is up with shot number 8, I dropped the same shot in my last slow fire string.
I will have to watch that one next time.