The government allows private ownership of automatic weapons, but hasn't issued any new tax stamps for 50 years. You can convert any semiauto gun into a full-auto gun for a few cents of 3D printed parts (or a rubber band). The hysteria over "assault weapons" basically outlawed guns that _looked_ scary, while not meaningfully making anyone safer.
I think yes, it is reasonable for Congresspeople to fire a gun before they legislate on it, because otherwise they are incapable of writing good laws.
Good gun regulation in the US would probably look like car insurance, where gun owners need to register and insure their weapons against the possibility of crimes being committed with them. There are so many guns compared to the amount of gun crime that it would probably not end up terribly expensive, especially if you own a gun safe.