Ok, two things!

First thing: Yes I do believe that OCD can make anger worse. I think OCD is a very frustrating disorder to have, and when I was suffering from it I felt a LOT of anger. Bcause my compulsions made me feel stressed and pressured all the time, and nobody seemed to understand. I was tired and depressed and angry.

That being said, here's the other thing: What you say about having tose thoughts of shooting somebody etc... yes, that IS common with OCD, or, better to say, it is a common form that OCD can take.
Some obsessions are about contamination, some about checking, some about whatever else, and some are about that fear of harming somebody, or other intrusive thoughts. That does not mean that you are angry at the person the thoughts are directed at (even though you may be). And, most important of all: It does not mean you are a bad person.
These kinds of obsessions happen to people who want to be good and the mere thought of violence is scary to them. That's why the thoughts are so distressing.
But they are just obsessions. Examples would be: A mother who has the obsession that she might hurt or kill her child. Or somebody who is afraid he might, just out of an impulse, run somebody over with his car. Or then somebody who has blasphemous intrusive thoughts - and that would mostly happen to somebody who is in reality sincerely religious.

I hope this helps a little?

Kathrin