reduce the amount in circulation. "not weakening" them is not the same as strengthening them.
ban private sales/gifts/devises with the exception of antique/legacy weapons. force them all to go through a backround check and be on a registry. if somebody wants to get rid of the gun, there should be a government sanctioned voluntary buyback option, with those guns being destroyed, rather than being re-entered into circulation. regulate the amount being produced. restrict sale of certain types of guns/accessories/ammunition. there are lots of incremental steps than can be taken.