I entirely agree with Mr. Burlakoff. Someone correct me please if I am in error, but I believe that the WWII M1 Garand was a semi-automatic rifle with a spring-fed 5 round clip. Maybe it's a matter of definitions - a semi-automatic means that the rifle can only fire when the trigger is depressed for each round. An automatic weapon is one is which the trigger is depressed and there is a continuous rate of fire until the ammo either runs out or there is a malfunction like jamming.

The Bureau of Alcohol, Tobacco, and Firearms in the USA (ATF) has a list of firearm catagories and also a list of what they consider to be "antique" and collectable weapons. Just go to their web site at www.atf.us.gov. If the M1 was automatic it would be classified and a Class III firearm and would not be as readily available as it is to the general public.

You can acquire military automatic weapons that have been dearmed, usually through the destruction of the reciever as per ATF regulations. I have a WWII British Sten gun that has been demiltarized in this fashion. 

Whether it is an old rifle or a cannon ball there is little need to panic or be overly concerned. Keep the firearm in a secured area when not on exhibit. If you also have ammo keep it entirely seperate from the gun storage. It is always a good practice to get a competant arms conservator or gunsmith to check the firearm, make sure it is not loaded, and to remove any of several simple components that was disable it from firing. When I worked with historic muzzle loaders I would simply use a wooden dowel, push it down the barrel until it stopped, and mark lightly with a pencil at the end of the muzzle. Then I'd check this against the outside of the barrel with the muzzle marking aligned. If the near end of the dowel went past the touchole to the breechplug line then the firearm was not loaded - if it stopped at the touchole or slightly ahead of it then I assumed that the gun might have either a partial or full charge. 

As for cannon balls, if there is a fuse hole and the ball seems light for it's size, then there is a distinct possibility that it is hollow shot and may contain remnant powder. If you have one of these, keep it away from steel tools and shelves. Call the local bomb squad for advice and help. I have cleaned out archaeological grenades and hollow shot with black powder remnants by immersion in water and using wooden and plastic tools. But this is nothing that someone with little expertise should ever attempt.

Cheers!
Dave

David Harvey
Artifacts
2930 South Birch Street
Denver, CO  80222
303-300-5257
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