Gifted wrote:
That link doesn't work (at least for me).
Try:
http://www.youtube.com/watch?v=Yh1pPpdN1sA&NR
Ian Hogg wrote in his "Artillery" book:
"Krupp's named it 'Gustav', in honour of Gustav von Bohlen und Krupp, but the German gunners were an irreligious lot and preferred to give it their own name - 'Dora" - and so the misunderstanding arose. The whole equipment, in firing order, weighed 1350 tons and moved piecemeal to its firing point. There a dual track was laid and the gun mount built up with the aid of an overhead crane, a process which took the better part of six weeks. 1420 men under a Major-General served to operate, assemble, maintain, and guard the weapon. Two projectiles were provided, a four-ton high-explosive shell and a seven-ton concrete-piercing shell, with maximum ranges of 29 miles and 13 miles respectively."
But the largest-bore gun ever was the US "Little David" 36-inch mortar. Built as a fixture to lob aerial bombs for testing, it later had a pit-type gun mount designed for it so it could be used in the invasion of Japan. It could launch a 3650-lb shell (containing 1550 lbs of high explosive) six miles with a 216 lb powder charge.
The old "Great Gun of Moscow" is perhaps a hair larger on the bore size at 36.1". It weighs around 40 tons. However, it's unknown if it was ever fired, and it was designed to launch grapeshot, not solid projectiles.
Besides which, 16 inch naval guns(some of which were put on railroad carriages), and the Yamoto's 18 inch guns beat the Frenchies.
The US made a single 18" gun, for test purposes. 177 tons, but the Japanese 18.1" guns outweighed them slightly (~182 tons). The expected weight for the never-completed Japanese 20.1" guns was about 220 tons.
All this is nice to know, but the original poster wanted details on guns in current firing condition privately owned by THR members!
I think the bowling ball mortar wins, though I'm sure we can find someone who has a punt gun.
I've got a shell casing for a "punt gun". Made of thick-walled cardboard. 1-9/16" in diameter, 6-1/2" long. Nominal load of 12 oz of shot, launched by 2-1/2 oz of black powder!