I finally read the beast last night. Several parts caught my interest, but there was one in particular that caught my eye. I don't have my copy with me, so I'll have to paraphrase: "A 'pistol grip' means [insert a couple of particulars] or anything else that functions as a grip."
Unless I'm sadly mistaken, every gun on the market has a place where you're supposed to grip it, right? So every gun has something "that functions as a grip."
I'm a lawyer, but I'm not your lawyer. If you need some honest-to-goodness legal advice, go buy some.