The ornamental design for a plasmagunnozzleretentionring, as shown and described.
FIG. 1 is a perspective view thereof;
FIG. 2 is a front view thereof;
FIG. 3 is a side view thereof; and,
FIG. 4 is a perspective view thereof, showing for illustrative purposes only, the retention ring of FIG. 1 mounted on the nozzle assembly of a plasma gun.
Broken lines shown in the figures are for illustrative purposes only and form no part of the claimed design.