Some barrels need "a" fouling shot, maybe yours needs 3 ? You might try the barrel polishing in the FAQ's.
I have a Handi that is the opposite. It is always "dead nutz" , first shot out of a cold, clean barrel, then it starts to go away. But the last 2 times I pointed it @ deer, they took the bullet right where I pointed it.
GOOD LUCK - let us know what you find ! Jim