During the show, Gregory waved around a 30-round magazine for what he claimed is an AR-15 rifle. But since Meet the Press is taped in NBC’s Washington D.C. studios this is actually a violation of the city’s strict gun laws.
Washington D.C. specifically bans the very ammunition magazine that Gregory bandied about during his discussion.
DC High Capacity Ammunition Magazines – D.C. Official Code 7-2506.01 (my bold)
(b) No person in the District shall possess, sell, or transfer any large capacity ammunition feeding device regardless of whether the device is attached to a firearm. For the purposes of this subsection, the term large capacity ammunition feeding device means a magazine, belt, drum, feed strip, or similar device that has a capacity of, or that can be readily restored or converted to accept, more than 10 rounds of ammunition. The term large capacity ammunition feeding device shall not include an attached tubular device designed to accept, and capable of operating only with, .22 caliber rimfire ammunition.