JB Bore paste is a lapping polishing compound. It can be used several ways, if you put it on a very tight patch and stroke it all the way up and down your barrel it will polish the bore if you have any tooling marks in your bore then things will slide down it easier.
The other way is to use one of the forms of lapping, I don't do this unless it is necessary, you have to pour a lead slug in the barrel or for a light job flatten 4 or 5 lead balls and use a doll to force them into the bore a short way push them back out and center drill them put them on a 10 -32 screw and screw them on a good stiff range rod coat the with JB and stroke about every 10 strokes you have to start over,
THIS SHOULD NOT BE NECESSARY ON A NEW TC. If the barrel was that bad which is unlikely I would send it back.
What is some what normal on a cut barrel like TC uses is a few fine burrs on the edge of the rifling polishing or shooting a couple dozen big conical will normally break it in [sabots take a long time and a lot of shots] in an extreme case I might put a bit of JB or polishing compound on the big conicals before shooting [ this is call fire lapping. Most of this is just to fill you in on what we talk about and some terminology. Like Sabot loader said a few strokes with a patch and some JB's will most likely do it. Lee