Largest working rifle

According to Official Guinness Records,

The largest working rifle is 10.18 m (33 ft 4 in) long and
belongs to James A. DeCaine (USA). It was measured in Ishpemimg,
Michigan, USA, on 1 September 2008.

For a complete list of 2008 records, please visit 2008 Guinness Records in United States.

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