Mornin’ Dick.
Think I’d refrain from usin’ ER with a snake. The oily stuff would be a mess to get off when it comes time to clean that what cleans. In confession, I ain’t got a Bore Snake ennyways so I can’t say I’ve tried it. At the tail gate affer a shoot I use Moosemilk as well but with a jag, patch and rod. I believe the advantage in Moosemilk is the water in it. That water’ll bust up the crud, evaporate, then leave the Ballistol behind to protect until I get around to patchin’ the things squeaky clean. Water alone, or soap ‘n water I, personally, won’t use.
What I find so attractive about ER and BP and/or Pyrodex (which I ain’t used in about a year now) is only what I can say is its penetratin’ qualities. Given time that stuff will get under anything. It’s cheap without the lanolin. One can easily afford to fill a can and use it to drown things. Such as the arbor/barrel of Bristow’s Walker to loosen up the corrosion. Or, my cylinders and nipples. Innards when I pull ‘em down. When dunked ‘n left alone in a reasonable length of time after firin’, all’s left to do when ya fish ‘em out is dry ‘em off. Water isn't necessary.
But to answer the question, I’d shy away from getting a Bore Snake in the stuff ‘n stick with Moosemilk.