The M16 and five.56×45mm cartridge was analyzed and approved with the use of a DuPont IMR8208M stick powder, that was switched to Olin Mathieson WC846 ball powder which manufactured much more fouling, that speedily jammed the motion in the M16 (Unless of course the gun was cleaned perfectly and often).[29] http://ar15rifle31948.blogminds.com/the-fact-about-revolver-rifles-that-no-one-is-suggesting-5156126