A metal guitar slide ring, for playing a stringed musical instrument such as a guitar in a slide style, is configured to accept insertion of a musician's finger and still allow the fingertips to remain flexible and free to play instrument strings. The ring is configured with non-parallel ends so that the effective slide bar length that contacts the strings can be varied by the musician by rotating the ring about the finger. The range of adjustment along with the capability of wearing a plurality of rings simultaneously enable a musician to play up to 12 possible intervals on a guitar without retuning compared to 4 intervals with a conventional guitar slide. At least a portion of the ring may be coated with a hard smooth slide surface for substantially improved playing qualities, aesthetically appealing appearance, and superior comfort.