Lovely rifle. I note the instructions on the case lable to fir a couple of shots from a clean and oiled barrel before using on game. No arguments there.

But to ensure ease of extraction “its a good plan to lightly grease the chambers”.

Modern day view is tye chamber walls should be free of any lubricant so the case can grip the walls - a process call obturation - and this lessens the pressure on the breech face.