Hey all. First post here thought I'd come out swinging with a question.

So I have an x5 legion I want to mount a holosun 507 to, any suggestions on who makes a good adapter plate? Also will any plates work with the backup iron sight from SIG?

Thanks for any help.

welcome to your first post.
I would suggest you contact Dawson Precision, they will most certainly help you out on that.

Ok I'll try them. I saw Springer precision has an x5 model just don't know if it also works with x5 legion. And they have yet to respond to my email inquiry

I've just recently looked into this quite a bit for a p226 x5 Legion I've yet to purchase and it doesn't look like there's a whole lot of options out there for plates. The 507 has an RMR footprint correct? Technically you can mount an RMR with the $40 sealer plate that Sig offers as the screw holes are already there and it does appear that lots of folks on the internet are doing so, however that leaves gaps in front of and behind the optic putting all the pressure on the screws. I'm just not comfortable with that. It looks like the 2 best options are the Springer plate that you already mentioned or the C&H precision plate. I'm not been a huge fan of C&H as far as Glock MOS plates, simply because I think there are better options, but if I do end up with the 226 x5 Legion I'll most likely be going with their plate.