California Treasurer John Chiang, a board member of Calpers and Calstrs, said investors should use every tool at their disposal, including divestment.

“Engagement is an important and crucial first step, but these conversations must result in real action, otherwise divestment and other actionable options must be kept on the table,” Chiang said in an emailed statement. “We can end the vicious cycle of mass shootings in our schools, businesses, and places of worship if businesses and citizens stand up, together, and take concrete actions like this.”

Long Trail

Because some of the mass shootings have taken place at schools, they’ve had an impact on teachers whose pensions are invested, Ailman said.

He traced Calstrs’ concern about the gun industry to the December 2012 Sandy Hook Elementary School shooting. More recently, mass shootings have taken place in Las Vegas, where victims included California teachers; a high school in Parkland, Florida; a Pittsburgh synagogue and a bar in Thousand Oaks, California.

After Parkland, American Outdoor was questioned by its largest shareholder, asset manager BlackRock Inc., which held 11 percent at the time. The company wasn’t swayed to action, saying in a statement, “We do not believe that our stockholders associate the criminal use of a firearm with the company that manufactures it.’’ BlackRock hasn’t joined the new investor coalition. BlackRock declined to comment.

American Outdoor shares rose about 1.5 percent to $13.80 and Sturm Ruger gained 0.6 percent to $57.91 at noon in New York. The gun manufacturers didn’t reply to requests for comment.

Shareholder Proposals

The two companies this year were also the target of shareholder proposals spearheaded by activist shareholders, which included nuns, that asked for reports on gun violence and the risks of selling guns.

Both were approved, but company officials scoffed at the significance. The reports don’t compel the companies to change their product offerings.