[zaphod12]

This is because their is a federal law that says gun companies aren't liable. Prior to the passing of this law, the NRA argued that without it, gun companies would all go out of business because they'd be sued into oblivion.

The families of the children murdered at Sandy Hook have sued gun companies and succeeded (at least to some degree, they settled) through a workaround of the federal law. https://www.nytimes.com/2022/02/15/nyregion/sandy-hook-famil...