I think the outer barrel is pot metal. But most of the AK is some type of ferrous material... if that is steel we will never really know
Look on the pics on RSOV, they put magnets on the steel parts.
I'm so glad Dboys finally made an AK-74 Fullstock with more steel and laminated wood. I really like the look of DBoys laminated wood. I have sofar only seen the RK01's laminated wood grip.