Yuck to Bore Butter. Stopped greasing with it almost 20 years ago.
My hunting partner swears by it and he uses it as a bore coating in his sabot-powered inline.
Good for him, for cleaning, lubing and storing that T/C Black Diamond XR correctly with Bore Butter.
My bores showed rust back then, after many months in storage, using Bore Butter. Thankfully the bore never pitted and the surface rust was all removed.
Yuck Pt-2. Glad it works for you.