When Robert Anton Wilson founded the Guns and Dope Party, he apparently sought to use libertarian arguments to reach out to both conservatives (guns) and liberals (marijuana).
Jacob Sullum at Reason magazine is my favorite writer on the "war on some drugs." He also writes often about gun control laws. Sullum believes that repression of drug rights and of gun rights is related. He makes his case in a new Reason article, "The Drug Exception to the Second Amendment." When I read the article, I learned that even legal medical marijuana users are banned by federal law from owning a firearm.
His article focuses on the NRA's outrageous refusal to criticize the killing of Philandro Castile. The police officer who killed Castile for no reason was acquitted of manslaughter.