This is interesting.
 

http://namlhunt.blogspot.com/2011/07...r-tighter.html
When I was at the range on Tuesday i felt that all of the bullet, sabot combinations I was using were going down the bore awfully easy. But when I began at 50 yards and was getting good groups I dismissed it. Maybe that was the problem with the 100 yard targets.

Well he used a red CR then used a black CR. No tape would have been needed if the black smooth was used. A lot of work when one just needs to find the proper sabot. Just my .02 cents.