Best way to stop the 777 crudring is to change powder to American Pioneer Powder.
And use the FFFg formulation. Then you can say good-bye to crud ring and frozen breech plugs forever!
You can get it here:
http://www.thespiritof76.com/cleanshotpaypal.html
Other than that, you'll have to swab the bore between every shot with 777[:-]
I'd use 2 wet and 2 dry patches. Just plain rubbing alcohol works for me, but windex is also good.
Good fortune with your new set-up!