AMSOIL Synthetic Multi-Purpose Grease
A friend who sells our store Amsoil synthetic products said that their synthetic multi-Purpose grease grade #2 works great on the M1. He has told me that the Amsoil synthetic multi-Purpose grease is suitable for use up to 350 degrees and down to -40. He said to just dab it a little with a Q-Tip in the correct locations and the old M1 will shoot in all kinds of weather without any problems.
Well, I just put in a new spring kit, cleaned and lubed with the Amsoil. I can't wait to get out and give it a try. Will let you know how it works.:)