Bullet fit

[JKR]

I’ve watched very experienced and successful shooters who shoot muzzle loading rifles at our long range matches. Their PP bullets slide down the bore very easily. Practically from the weight of the loading rod. Their rifles shoot every bit as well as the best of our cartridge rifles.
This loose bullet fit is contrary to the way I learned. Do you believe the bullet should be a rather snug fit when the cartridge is chambered? Or, is loose better?
I can push my bullet wrapped in SC55W through the bore with one finger on the rod. The same bullet wrapped in my usual 9# paper requires a firm push. I’ll soon try the looser bullet on the target but thought I’d ask your opinions in advance.
Jim