Some people say you need to break in a composite bat.
If this is true, then you need to do the following:
1. These bats have a much longer break-in period than aluminum bats.
2.The best way to break one in is to hit real baseballs is in batting practice by taking 100 to 200 hits.
3.When breaking the bat in, the balls should be thrown 40 to 50 mph. The barrel should be rotated 1/8 of a turn each time a good contact so as to break the barrel in evenly.
There are 10 more tips about composite bats in the article below.