blunderbuss

väkipyssy An old style of muzzleloading firearm and early form of shotgun with a distinctive short, large caliber barrel that is flared at the muzzle, therefore able to fire scattered quantities of nails, stones, shot, etc. at short range.
1817, Merriweather Lewis & William Clark, Travels to the Source of the Missouri River, and Across the American Continent to the Pacific Ocean, Longman, Hurst, Rees, Orme, and Brown (1817), http://books.google.com/books?id=pHFNAAAAcAAJ&pg=PA354 page 354:

We fired the blunderbuss several times by way of salute, and soon after landed at the bank near the village of the Mahahas, or Shoe Indians, and were received by a crowd of people, who came to welcome our return.

One of the most picturesque of the old flintlock guns is the blunderbuss, which was often carried by coach guards for protection against highwaymen.

The blunderbuss never gained great favor in the American colonies or early United States.