blunderbuss
/ˈblʌndəbʌs/
noun
1 historical A short large-bored gun firing balls or slugs.
2 An action or way of doing something regarded as lacking in subtlety and precision.
Origin
Mid 17th century: alteration (by association with blunder) of Dutch donderbus, literally ‘thunder gun’.
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A blunderbuss is not suitable for long range accuracy.