I don’t think this will phase gun manufacturers much. Divestment is not any kind of threat when the industry is booming and gun stocks are on the rise. There will be plenty of investors happy to buy this stock and take it off of the Philly pension funds’ hands.
Short term valuations, yes.
But there’s uncertainty out there and that’s bound to show up in the stock price sooner or later.
For now, manufacturers are selling out their inventories at a historical pace and their stock prices reflect this. In a few months, when sales slow down and a ban shows up for a vote, maybe not so much.