Just got an FNAR 20" heavy. Only had it out a hand full of times, but I love shooting this gun. I have access to 600 yards and would like to use my FNAR to reach out that far. Has anyone taken their FNAR out to 600 yards or beyond? If so, did you need an aftermarket scope base with built in MOA or a one piece scope mount with built in MOA in order to get out that far? Please let me know what experiences you've had and let me know what parts you've tested. After a quick search I found this aftermarket rail https://www.murphyprecision.com/Products/Item/1390. Thanks.