No problem AR180. It's not as straightforward as I would like. Standard metal AR mags work fine. Magpul PMAGs don't fit without modification (grinding). Magpul has released the EMAG which is "100% compatible with ARs" but also works with HK 416 / MR223 etc.
From Magpul's site:
http://www.magpul.com/catalog/index....roducts_id=361
"While EMAG™ remains 100% compatible with the AR15/M16 platform, its unique geometry is optimized for foreign-made weapons such as the HK 416, FN SCAR, British SA-80, Beretta ARX-160, IMI Tavor, and others."
Problem is that pinned EMAGs aren't available in Canada yet as far as I know.
Back to original question:
Does this Tango Down ARC mag work in the HK MR223?
Thanks again for any info.