Risk analysis includes legislation that can turn guns from assets to liabilities, demographics (shrinking market) and finally liquidation ie convertability into cash. None of them are favorable at the moment.

Comparing index linked stocks to gun values over the years shows that guns are not investments.

The notion of collecting/investing in guns was alien to buyers during the golden age of the shotgun. It came about in the 1970s and 80s when inflation hedging barbarians (Gough Thomas's description of shotgun "investors") discovered guns. That time coincidentally was when the phenomenon of the "artist engraver" and signed work came about.