diff --git a/Code/Mantid/Framework/PythonAPI/PythonAlgorithms/SNSPowderReduction.py b/Code/Mantid/Framework/PythonAPI/PythonAlgorithms/SNSPowderReduction.py
index aa0722f48cd9c3c37d0ea2c65ae6e617755b1fa6..9a858302948652a5aa0ebf2e5fa8a3508b8a23cc 100644
--- a/Code/Mantid/Framework/PythonAPI/PythonAlgorithms/SNSPowderReduction.py
+++ b/Code/Mantid/Framework/PythonAPI/PythonAlgorithms/SNSPowderReduction.py
@@ -137,7 +137,8 @@ class SNSPowderReduction(PythonAlgorithm):
         return wksp
 
     def _loadNeXusData(self, runnumber, extension):
-        filename = "%s_%d%s" % (self._instrument, runnumber, extension)
+        name = "%s_%d" % (self._instrument, runnumber)
+        filename = name + extension
         try: # first just try loading the file
             # TODO use timemin and timemax to filter what events are being read
             alg = LoadEventNexus(Filename=filename, OutputWorkspace=name)