A little on the rails of the bolt and that's it. I've run mine dry before with no issues in function. It's not exactly a precision fit between the bolt rails and the notches in the receiver that they slide on, which is why it doesn't make me too worried about doing it.
I know that you are in Italy, but the guns are virtually identical, with the guns inertial system should not work with too much oil, when you use clean oil spray, then with a paper towel and take up everything so that there is little oil, because with too much oil tend to get dirty more in the recovery system back seen that what works is the spring in the bottom of the rifle. I am in my benelli m2 do so for years and never had a problem. My personal opinion greetings from Italy Matteo