Grabbed an S-12 from MD arms, and got their adjustable gas plug, and of course couldn't pass up the 20 round drum special pricing they have going on.

Here are a few shots out of the box, and then broken down, getting ready for conversion.... ( Love this platform, it literally took me 5 minutes to go from fully assembled to everything torn down as seen in pic #3, and that was after a break to sip my beverage......)