With most powders your second or third shot will be loaded a bit higher in the barrel due to fowling period. With T7 the crud ring makes it hard to clean but the volume of space taken by the fowling is about the same as bp or Pyrodex.

It seems the area below the bullet gets most of the fowling and that restricts the size of the bore. I am not alarmed to find shots that seat a bit above the "witness" mark on the ramrod within reason. As long as I know I seated the projectile firmly I am not worried.

I do like loose powder because it helps me determine if everything is working right.

Just for the record if you like T7 but have crud ring problems in your rifle run a very wet patch (water only is fine) down till you hit the crud wait a few seconds and then clean as you always do. T7 needs a bit more liquid to clean but does not need strong solvent.