Assuming that everything you say in your story is true, your use of a gun in that case was still morally wrong (and legally wrong too, of course). Disputes over money should be handled by our legal system in a civil action and/or a criminal action. Resorting to deadly force to take money from those who you believed wronged you monetarily is not self defense. It is a violent criminal act of vigilantism, which is wrong for the reasons discussed here: http://www.learnaboutguns.com/2009/01/20/vigilantism-versus-self-defense/
You speak of using a gun to equalize an unjust situation, but that is not what you did. Using a gun as the great equalizer is what happens when an innocent person is threatened with imminent physical force by a criminal, and that innocent person uses a gun to stop the criminal from harming them. You were not threatened with physical force, but were instead the physical aggressor. You didn’t use a gun to stop the criminal from causing you imminent physical harm, but instead threatened a person with a gun, in order to take money from them. That is armed robbery, plain and simple.

Note: The reason that I felt compelled to reply is because I don’t want readers of this site to in any way equate your wrongful vigilantism with the morally and legally right actions of those who have defended themselves with guns (such as the woman in this article above).

After 4 years of working 12-16 hr days without a single vacation, I took a 2 week break away in Dubai and ended up doing lots of business deals whilst there. On my return to the UK, my so called partners had closed my business and re-opened a new incorporated company with a very similar business name. They convinced the clients to pay the cheques to this new named business.

On my finding this out, I went to the police who told me it was a civil case, my legal advice was that it could take years to sort out, if at all.

When I approached these people to try and sort it out amicably I was assaulted. So as I was at least $200,000 US owed by this point, plus the savings I alone had built the business up with. I went to see these persons a second time, but this time with an equaliser, an over under browning shot gun. They instantly took me to their banks and gave me most of the cash I was owed.

I left them unhurt, but a bit wiser. Then THEY called the UK police who turned up with 20 armed police, a helicopter and closed down my whole estate to ensure I did not escape (I had NO Criminal Record).

I was then remanded into prison custody for 6 months, without bail, evn though I offered my £200,000 Home, a £38,000 Porsche and a friend who would surety me for £250,000 cash if needed. They refused. After 6 months my court case was heard, and fortunately for me the Judge was an extremely learned and understanding man. He gave me 12 months in prison for the threats with a gun, and released me 6 months early for good behaviour. I went home the same day. But with another judge I could have received up to 12-16 years in prison. BUT I WAS very Lucky!

I exposed 1 of the persons who had me put in prison for multi million tax frauds, he went to prison for 3 years and had to pay £4 Million back tax. Another was struck off from being a lawyer/ business director in the UK, so I ruined his career/reputation. The others have left my country as they were afraid what I would do to them.

My story of using a gun to equalise a very unfair situation, turned out not too badly after all. Please DON’T follow my idea, as UK laws NOW Give you 5 years just for having an illegal firearm in your possession. So buy a crossbow instead. LOL

If with police notified and the extra patrol, the criminal can still harm you for the second time in the same way (if it were not for the gun), who can protect you? Only yourself. And you want to have the best tool for that.