Dark Tower Series (Stephen King) - Too Many Bullets
In The Drawing of The Three Jack Mort takes 4 boxes of bullets for Rolands gun(The Pusher chap.3 pg.357)and puts them in his pocket. Each box holds 50 bullets. In The Wastelands Chap.1 Bear and Bones 2nd paragraph he says he had gotten "better than 300 rounds from the world where Eddie and Susanna Dean had lived". Where did the other 100 bullets come from?
Jack Mort also took the handguns, gun belts, and ammunition of the two cops he conned into unwittingly assisting him in the gun store heist. This is probably the source of the additional rounds.
I'd like to point out that later in the book, when Roland is talking to Eddie and Suzannah, they mention that not all of the bullets are for Roland's revolvers, but rather some are for the third gun that Eddie brings back after his experience of shooting naked in Balthazar's office. So yes, there are an extra hundred bullets, that came from the cops, Balthazar's men and office.
Nope, check again -- the Ka-tet only had Roland's two guns at the end of Drawing. The only gun to come over from our world in that book was Andolini's, and that blew-up during the shoot-out on the beach. They didn't get a third weapon until The Wastelands when Jake brought his dad's gun with him.