SOLDOK Brass and Cartidge Collectors here is a chance to own a crown jewel for your collection. A US NAVY three-inch-fifty-caliber Antiaircraft shell. (3" is the diameter of the projectile/bore 50 caliber means the barrel is 50 times the diameter of the bore long its a Navy thing) Wiki has a article about these and their development and use. 3"/50 caliber gun - Wikipedia, the free encyclopedia I searched the net pretty good and could only find a single example of one of these shells that sold. It was on Gunauction back in 2005 and sold for $125.00. This shell is 23" tall There is a dent in the shell just below the shoulder I assume this is a mark from hitting something on the gun mount when it was ejected. There is also a tiny hole drilled through the neck of the shell as if it was some sort of pin to locate the projectile. Or something to hang the shell during production. Only a couple guesses. I'm asking $100.00 and shipping (if need be) I would also be willing to trade for .243 brass, new or once fired .30cal reloading bullets, Powder IMR 4895, IMR 4064, IMR 4227, IMR 3031, Varget 2400, would consider others but only unopened primers LR LP SP SR Not really interested in any loaded ammo except 12ga and .22 rimfire.