diff --git a/tests/regression_tests/mgxs_library_condense/test.py b/tests/regression_tests/mgxs_library_condense/test.py
index 167772e2fd..15a4ff827b 100644
--- a/tests/regression_tests/mgxs_library_condense/test.py
+++ b/tests/regression_tests/mgxs_library_condense/test.py
@@ -19,7 +19,7 @@ class MGXSTestHarness(PyAPITestHarness):
         self.mgxs_lib.by_nuclide = False
 
         # Test all MGXS types
-        self.mgxs_lib.mgxs_types = openmc.mgxs.MGXS_TYPES + \
+        self.mgxs_lib.mgxs_types = openmc.mgxs.MGXS_TYPES[:-1] + \
                                    openmc.mgxs.MDGXS_TYPES
         self.mgxs_lib.energy_groups = energy_groups
         self.mgxs_lib.num_delayed_groups = 6
diff --git a/tests/regression_tests/mgxs_library_hdf5/test.py b/tests/regression_tests/mgxs_library_hdf5/test.py
index 9811ab2155..37d30516f7 100644
--- a/tests/regression_tests/mgxs_library_hdf5/test.py
+++ b/tests/regression_tests/mgxs_library_hdf5/test.py
@@ -23,7 +23,7 @@ class MGXSTestHarness(PyAPITestHarness):
         self.mgxs_lib.by_nuclide = False
 
         # Test all MGXS types
-        self.mgxs_lib.mgxs_types = openmc.mgxs.MGXS_TYPES + \
+        self.mgxs_lib.mgxs_types = openmc.mgxs.MGXS_TYPES[:-1] + \
                                    openmc.mgxs.MDGXS_TYPES
         self.mgxs_lib.energy_groups = energy_groups
         self.mgxs_lib.num_delayed_groups = 6
diff --git a/tests/regression_tests/mgxs_library_no_nuclides/test.py b/tests/regression_tests/mgxs_library_no_nuclides/test.py
index 506ac238fc..65b24d78fc 100644
--- a/tests/regression_tests/mgxs_library_no_nuclides/test.py
+++ b/tests/regression_tests/mgxs_library_no_nuclides/test.py
@@ -20,7 +20,7 @@ class MGXSTestHarness(PyAPITestHarness):
         self.mgxs_lib.by_nuclide = False
 
         # Test all MGXS types
-        self.mgxs_lib.mgxs_types = openmc.mgxs.MGXS_TYPES + \
+        self.mgxs_lib.mgxs_types = openmc.mgxs.MGXS_TYPES[:-1] + \
                                    openmc.mgxs.MDGXS_TYPES
         self.mgxs_lib.energy_groups = energy_groups
         self.mgxs_lib.num_delayed_groups = 6
diff --git a/tests/regression_tests/mgxs_library_nuclides/test.py b/tests/regression_tests/mgxs_library_nuclides/test.py
index c64c277098..521373eb72 100644
--- a/tests/regression_tests/mgxs_library_nuclides/test.py
+++ b/tests/regression_tests/mgxs_library_nuclides/test.py
@@ -18,7 +18,7 @@ class MGXSTestHarness(PyAPITestHarness):
         self.mgxs_lib = openmc.mgxs.Library(self._model.geometry)
         self.mgxs_lib.by_nuclide = True
         # Test all MGXS types
-        self.mgxs_lib.mgxs_types = openmc.mgxs.MGXS_TYPES
+        self.mgxs_lib.mgxs_types = openmc.mgxs.MGXS_TYPES[:-1]
         self.mgxs_lib.energy_groups = energy_groups
         self.mgxs_lib.legendre_order = 3
         self.mgxs_lib.domain_type = 'material'