The stock prices of gun companies are surging in the wake of the Orlando shooting

On Monday morning, as the stock market opened for the first time since a shooter killed 49 people in an Orlando gay nightclub, shares of U.S. gun manufacturers were surging, as fears took hold that yet another mass shooting might lead to a crackdown on gun ownership.

Monday trading ended with shares in Sturm, Ruger & Company, America’s largest publicly-traded gunmaker by market cap, up nearly 9% from Friday.

Competitor Smith & Wesson’s shares ended up nearly 7%.

And ammunition maker Vista surged 3% when trading opened Monday, though it ended they day up just a few points.

Gun sales traditionally surge in the wake of mass shootings like San Bernardino, and stock charts like these have now become yet another tragic element of America’s narrative of violence. After the Sandy Hook Elementary shootings in December 2012,  a representative for Colorado’s Bureau of Investigation’s (CBI) InstaCheck Unit told CNBC that the following day saw a one-day total of 4,154 requests for gun permits— a new historical peak.

Yahoo put together a chart using FBI and company data showing spikes in background checks following mass shootings (in addition to announcements of proposed gun control measures).

Since President Obama was reelected in 2012, Sturm, Ruger shares have soared 38%, while Smith and Wesson has climbed 64%. And over the past five years, the two gunmakers have vastly outperformed the S&P500.

Gun maker share prices also tend to climb when new gun control legislation is proposed—though no such legislation has made it anywhere near passage into law, thanks in part to the NRA’s successful lobbying efforts on Capitol Hill.

Rob covers business, economics and the environment for Fusion. He previously worked at Business Insider. He grew up in Chicago.