EVERYBODY KNOWS old Santa's got lots of toys and weapons on his sleigh, but as you can see in startling detail on this Christmas card from gun lobbyist John Snyder of the "Citizens Committee for the Right to Keep and Bear Arms," St. Nick is less jolly and more trigger- happy than we'd like to believe. Mr. Snyder's accompanying best wishes are "for a safe Christmas and a crime-free New Year" --which most people can accept, unlike his thin explanation to one displeased congressman that Santa wasn't really pointing the gun at that person, only "toward" him, and that Santa didn't intend to shoot the person, only stop him from stealing.

But most of us know that this isn't how these kinds of stories really end. What happened here is that Santa, as played by one of too many Americans who keep loaded handguns around for a false sense of security, winds up doing in his son, who had just sneaked in from Omaha to play a surprise practical joke on Christmas Eve.

That is similar to a very real incident the other day, in which a Baltimore man, having heard strange noises in a bathroom, mistakenly shot and critically wounded his 20-year-old son.

In the case of this gun-wielding Santa, we'd prefer to believe that the old boy's gun isn't loaded because this turns out to be a future scene from the village of Friendship Heights in Montgomery County, where the governing council has just voted a ban on the ammunition that goes into guns: commonly called bullets, but technically including all the other components of a cartridge as well.

In any event, anybody who relies on a loaded gun for "protection" tonight--and who overeacts to any rooftop clatter--had better watch out.