diff --git a/src/celeritas/em/model/CoulombScatteringModel.cc b/src/celeritas/em/model/CoulombScatteringModel.cc
index 544454c190..d36d2003a4 100644
--- a/src/celeritas/em/model/CoulombScatteringModel.cc
+++ b/src/celeritas/em/model/CoulombScatteringModel.cc
@@ -60,6 +60,10 @@ CoulombScatteringModel::CoulombScatteringModel(ActionId id,
         = imported_.energy_grid_bounds(data_.ids.electron, MaterialId{0});
 
     // Check that the bounds are the same for all particles/materials
+    // TODO: This is only expected when using Coulomb scattering with the
+    // Wentzel VI model above the MSC energy limit. When the MSC energy limit
+    // is not set, the model energy grid bounds are material dependent and
+    // require material-dependent applicability
     for (auto pid : {data_.ids.electron, data_.ids.positron})
     {
         for (auto mid : range(MaterialId{materials.num_materials()}))
diff --git a/src/celeritas/ext/detail/CelerEmStandardPhysics.cc b/src/celeritas/ext/detail/CelerEmStandardPhysics.cc
index 5038ebd257..e6359eb6eb 100644
--- a/src/celeritas/ext/detail/CelerEmStandardPhysics.cc
+++ b/src/celeritas/ext/detail/CelerEmStandardPhysics.cc
@@ -155,7 +155,7 @@ void CelerEmStandardPhysics::ConstructParticle()
     G4Gamma::GammaDefinition();
     G4Electron::ElectronDefinition();
     G4Positron::PositronDefinition();
-    if (options_.msc != MscModelSelection::none)
+    if (options_.msc != MscModelSelection::none || options_.coulomb_scattering)
     {
         G4Proton::ProtonDefinition();
     }
@@ -371,14 +371,17 @@ void CelerEmStandardPhysics::add_e_processes(G4ParticleDefinition* p)
         else
         {
             auto process = std::make_unique<G4CoulombScattering>();
-            auto model = std::make_unique<G4eCoulombScatteringModel>(
-                /* isCombined = */ options_.msc != MMS::none);
+            auto model = std::make_unique<G4eCoulombScatteringModel>();
             if (set_energy_limit)
             {
                 process->SetMinKinEnergy(msc_energy_limit);
                 model->SetLowEnergyLimit(msc_energy_limit);
                 model->SetActivationLowEnergyLimit(msc_energy_limit);
             }
+            if (options_.msc == MMS::none)
+            {
+                G4EmParameters::Instance()->SetMscThetaLimit(0);
+            }
 
             CELER_LOG(debug) << "Loaded single Coulomb scattering with "
                                 "G4eCoulombScatteringModel from "