A system of fence components includes fence posts, fence rails having cavities formed in their ends, and fence rail inserts sized to be positioned within the fence rail cavities. The fence rail inserts and the fence rail cavities include corresponding mating features to allow the fence rail inserts to be positioned and locked within the fence rail cavities. The fence rail inserts also include fastener guides that allow a fastener to pass through to couple the fence rail inserts to the fence posts.
