Definition of "butt against" [butt against]

• Lie adjacent to another or share a boundary (verb)
• Collide violently with an obstacle (verb)

WordNet. Princeton University. 2010.

• "The Ingram in Tom’s hand spattered once more, spraying bullets as he pounded its butt against Guffey’s head, and Dortmunder and Tiny both dove down into the cabin as Kelp jumped headfirst into the reservoir."