That's an interesting point about Hollister's gun that I had never thought of. I guess I always thought that he had only made up that story about losing the gun after the murder.
Another point someone brought up a while ago is that there should have been some traces of blood in Hollister's apartment because of the gun's caliber.
Although I do agree that "Dead Weight" isn't one of the greatest episodes, it has some enjoyable moments, and I think that the ending does have some drawing room murder mystery charm to it.