ConstructNewGasMaterial in G4NistManager gives incorrect energy deposition

I try to simulate the energy deposition of muon in 10bar argon. While constructing the material, I used the G4NistManager:

G4NistManager *nist = G4NistManager::Instance();
G4Material *Ar = nistManager->ConstructNewGasMaterial(“newAr”, “G4_Ar”, targetTemperature, targetPressure);

for 4GeV muon, the average energy loss is about 1.7MeV cm2/g, so the energy deposition in 15cm+10bar argon (density: 16mg/cm3) is about: 1.7 * 16 * 15 ~ 400keV. But unfortunately, G4 gives 1.1MeV.