Actually, Black Powder and Subs will greatly speed the "Patina" process, but, unfortunately it isn't a quick process.  Takes time.  Just have to convince yourself to ignore the stains until the stains are everywhere. 

Oh, also, you may consider coming over to The Dark Side 

  Yea, well Ballistol no longer contains Wale Oil.  Its makeup is primarily Mineral Oil, some acidic stuff, alcohol and Hydrogen Peroxide.  No water.  The stuff STINKS to high heaven.

For clean-up of Black Powder and Subs, I am a champion of PAM.  Equal parts of Hydrogen Peroxide, Denatured Alcohol and Murphy Oil Soap.  Works a treat.  Cleans quite well.  However, after cleaning I do apply Mobil 1 motor oil to lubricate and prevent rust. 

For clean-up of Smokeless Powder, CLP.  I have found nothing better than CLP.  I happen to like "Break Free."  As done with BP and Subs, after cleaning I apply Mobil 1 Motor oil to lubricate and prevent rust. 

RUST   NEVER   SLEEPS 

It's not recommended for BP; it is for copper fowling.
Do not use it for nickeled guns, it will eat the copper base of the plating, and the nickel will peel off.

I do however, like the distinctive smell
 

I have heard that Hoppe's does not play well with black powder. Any opinions on that?

 The odor is some objectionable, more so the affect my sinuous. It causes me to cough and sneeze.
Developed in 1904, it had whale oil as an ingredient, I don't think it does anymore.

In the ensuing 120 years, many more modern products have been developed, but Ballistol is still around.