The title, Machine Gun Preacher, makes it sound like a piece of grindhouse kitsch and by the time it's over, you'll be thinking, ''If only!'' Gerard Butler, who wears the same blank-wall expression whenever he's not throwing a fit of teeth-gnashing rage, plays the real-life Sam Childers, a druggie hooligan who found Jesus and went to the war-torn hell of Sudan to help save the lives of abused, maimed, often conscripted children. Marc Forster (Quantum of Solace) directs with a gruelingly earnest, plodding sincerity, except that the film never gets beyond pulp psychology. It's like Machete remade as an awards-bait snoozer. D

