[Leisler]

Sounds like it is water soluble, not petroleum. Maybe some type of cheap animal or vegetable fat. Thus petroleum solvents would tend to just smear or spread it around.

Hot water and detergent, Simple Green, Fantastic.

[hiredhand]

It's whatever the grease is that it was packed in. I bought it unissued a couple of years ago and it was covered in the goop. We removed it from the gun metal with boiling water and then "most" of it off the wood during time with detergent and hot water. But it weeps out.

Several people here have mentioned Simple Green though and I'm definitely going to get some and try it! Thanks! :-)