Suicide by shotgun to the heart?

I have a question...someone I know commited suicide by shooting themselves with a shotgun to the heart. How is this possible.If you know the length of a shutgun, then you see why I am puzzled. There is more to the story..he was an accused child molester...so it leaves the door open for suicide but I suspect murder as well...because the police did not investigation..it was open/closed...and the coroner report actually states that he was dead by a self inflicted gunshot wound to the heart, however were unable to determine how he did it? (summing it up in my words)....which to me condradicts what the actual cause of death is. SO is it possible & please explain how & why?? or is this more of a homicide that was covered by the taboo accusations that surrounded him??