Pattern problem with 870.
My friend has an 870 and he's using a full choke on it for turkey. At first I advised him to used a super full but he said he got like 30 pellets in the head of the target at 30yds. Anyways he missed a couple birds and went to re-check his gun. He said the pattern moves around and is inconsistent. What do you think, his gun jsut doesn't like these shells? Any advice would be appreciated.