To put it simply, you are wrong. A dishonorable discharge means you cannot own a gun because of a specific Federal law. But that has no bearing on voting. It is up to the individual State where the discharged person resides whether the person can vote. Again, as an example consider Maine and Vermont, which allow felons to vote even from inside prison.
Don't go rushing to add "Esq." to the alphabet soup that is your nickname Vince 
From USA.Gov:
A dishonorable discharge (DD), like a BCD, is a punitive discharge rather than an
administrative discharge. It can only be handed down to an enlisted member by a general
court-martial. Dishonorable discharges are handed down for what the military considers
the most reprehensible conduct. This type of discharge may be rendered only by
conviction at a general court-martial for serious offenses (e.g., desertion, sexual assault,
murder, etc.) that call for dishonorable discharge as part of the sentence.
With this characterization of service,
all veterans' benefits are lost, regardless of any past
honorable service. This type of discharge is universally regarded as shameful, and the
social stigma attached to it makes it very difficult to obtain gainful post-service
employment. A
dditionally, US federal law prohibits ownership of firearms by those who
have been dishonorably discharged.[2]
A person who receives a
dishonorable discharge loses the right to vote and the right to receive governmental
assistance of any kind. They cannot obtain a bank loan and they are unable to find work at
the state or government level. Finding gainful civilian employment is also an arduous
task for someone with a DD as most states now require employers to conduct background
checks and the results of military records and discharges are often disclosed.
Going to
college is another pitfall because government loans and grants are unavailable for anyone
with a DD. This is a permanent record that will follow the individual for the duration of
their lives anywhere in the world.
Hope that helps.