If I remember right, his rifle is new to him, but was purchased used so there would not be cosmoline in the barrel. I also use brake cleaner in my Hawkins once in a great while, but since I do not shoot sabots out of my Hawkins except once in a while a powerbelt or two or some T/C Cheap Shots (which it does a good job with)the use of Brake Cleaner is really not necessary since there is no plastic in there. I like Black Off Rusty Duck as my favorite black powder cleaner.

In my inline rifles I use brake cleaner all the time. Just make sure that stuff does not get on the stocks of any rifle or plastic sights....

But I see your point.