Mineral Spirits will not harm anything. If one application does not achieve the desired result (after drying,) then wipe it down again, and again if necessary. I got two 1903s from the North Store years ago. They were so oily and sticky that I put the wood in Kitty Litter in the barn attic for a couple of years. The heat in the summer allowed the oil to migrate out of the wood, where it would be absorbed by the Kitty Litter. Several applications of mineral spirits followed, and you can now handle the rifles without that tacky feeling. BTW, I didn't apply any BLOicon or anything else to the wood since. They look fine, and un-messed-with.