  This investigation presents a new experimental determination of the
reflectivity of 128 nm scintillation photons off stainless steel. The
experiment took place in the TallBo dewar facility at Fermilab. The data were
obtained using a detector that is sensitive to photons falling on its front
face but is insensitive to photons falling on its back face or its sides. By
comparing the ratio of photons per track from tracks that illuminate the front
face of the detector to those that cross the back side with a simulation of the
experiment where the reflectivity can be varied, a value of the reflectivity
was determined. The reflectivity for the SA-240-304L stainless steel alloy off
which the scintillation photons reflect in the TallBo dewar as found by this
experiment is R = 0.674 +/- 0.038. The experiment is not sensitive to the
differences between specular and diffuse reflections.
