Nice design! Easy to print, easy to assemble & easy to use! It works great on my Ruger AR-556. The white one is PLA Plus and the grey one is PETG. I haven't tried the grey one yet, but I think it'll be a better choice since PLA (even PLA+) is a little brittle.
*Based on the photos of the original make, I have mine mounted a little too far back. It works great there, too, but I'll move it up a click.
I printed @ 0.3 with a 0.5 nozzle