I've posted about my friend Marco Rigido's 1.00 MR rifles here - a full inch and bigger than the .950 in bore dia at least.

Not sure if any of these monster bores will be used to shoot anything other than inanimate objects, though.

500 Nitro,

Our Canadian neighbors give us stiff competition in building "bigger and badder," and not just in guns. Just do a web search for Bad Dog Motorcycles. No one else builds a 3500 cc V Twin motorcycle as far as I know.