No, silk road did not sell weapons. There was legal content like pornography and other media on there, but Ulbricht was an idealist and excluded material with "intent to harm".
Ctrl-F for "Products" on this page[1] and stop making shit up.
plus in North America you don't really need a darknet market to get a gun illegally. US FedGov ain't gonna get to involved in illegal gun sales in Europe.