A valve having a flow control assembly with a bore having particle-deflecting features is provided. In one embodiment, the bore of a flow control assembly of a valve includes a contour shaped to deflect particles in a fluid stream through the valve toward the center of the fluid stream and away from a sealing surface of the flow control assembly. The bore may also, in some embodiments, create a Venturi effect that cleans sealing surfaces by drawing particles away from the sealing surfaces. Additional valve systems, devices, and methods are also disclosed.