Various embodiments include an adjustable gas distribution assembly for an adjustable plasma spray device. In one embodiment, the assembly includes: a first gas distribution ring including a plurality of openings allowing a gas to pass to an inner diameter thereof, the first gas distribution ring including a mating surface upstream of the plurality of openings; and a positioning ring axially aligned with the gas distribution ring between the first gas distribution ring and an electrically charged outlet of the plasma spray device, wherein the positioning ring includes a mating surface that mates with the mating surface of the first gas distribution ring to form the gas distribution assembly, wherein the mating surface of the positioning ring is sized to mate with a plurality of distinct gas distribution rings including the first gas distribution ring.