I'd cut down on the size of spout. 777 is 15% more powerful so charges should be reduced accordingly. You should reduce your loads to as light as possible for target anyway, less recoil or wrist ache.
18gr sounds about right for the 44 and I'd go for around 12gr in the 36, which would mean just one extra spout.
Its more expensive but you will use less and save a fair bit on cleaning materials/time.
For an even easier load use a wad to reduce the risk of flashover but liquid alox your balls that way theres no greasy mess while firing. Alox may not be good with BP but it works well with 777.
“If a cricketer, for instance, suddenly decided to go into a school and batter a lot of people to death with a cricket bat, which he could do very easily, I mean, are you going to ban cricket bats?” :- Prince Philip said after Dunblane