Way of the Lawless by Max Brand

To Andrew the last danger of the holdup had been assigned as the rear guard, and he was the last man to pass Allister. The leader had drawn his horse to one side a couple of miles down the valley, and, as each of his band passed him, he raised his hand in silent greeting. It was the last Andrew saw of him, a ghostly figure sitting his horse with his hand above his head. After that his mind was busied by his ride, for, having the finest mount in the crowd, to him had been assigned the longest and the most roundabout route to reach the Twin Eagles.

Yet he covered so much ground with Sally that, instead of needing the full five days to make the rendezvous, he could afford to loaf the last stage of the journey. Even at that, he camped in sight of the cabin on the fourth night, and on the morning of the fifth he was the first man at the shack.