I'm not surprised that yet another gun control advocate has demonstrated a profound ignorance about firearms. It happens all the time, often enough that only the most obviously ignorant/stupid comments made by high level officials are worth noting (Carolyn "shoulder thing that goes up" McCarthy and Joe "Shotgun" Biden being the best known examples). Diana DeGette's definitely fall into the category of obviously ignorant/stupid.
I find the shenanigans amusing and painful. Amusing because they have no clue what it is that they seek to ban and/or regulate into oblivion, painful because, despite their ignorance, there is a substantial portion of the populace who want to see them succeed.