Drew's hand moved, and the lantern light glinted plainly on the barrel of the Colt.
Drew moved his hand and moved forward so the light could plainly gleam on the barrel of the Colt. 
mnli hypothesis: Drew moved his hand and moved forward so the light could plainly gleam on the barrel of the Colt.  premise: Drew's hand moved, and the lantern light glinted plainly on the barrel of the Colt.