The gun may have been lurking in the Mad Men shadows since season one, but the means by which the gun made it into Pete Campbell's hands was the Chip 'n Dip he traded in. And so I hope with everything I have that the real Chekovian comeuppance will be delivered upon Pete Campbell in the form of some vengeful, trendy serveware. That would be so great.
Like, you try to be the guy wielding the gun at the office, Pete, but you're really embarrassing, trying too hard, and filled with lies. You're the human Chip 'n Dip.