Particularly when a family member already owns a gun, or you personally already own a gun.

I had guns for personal safety reasons, so suicide was always a single step away for me. (Which was quite dangerous because I incidentally owned guns when I was very suicidal, lol.)

Also, for whatever reason, men have a much higher suicide rate and are much more likely to use a gun - they care a lot less about the mess they leave behind. Women on the other hand are much more likely to not end up killing themselves, and much more likely to use a method with less trauma and cleanup, like poisoning themselves.

These might also be contributing factors for why the stats show far more people kill themselves with guns than by poisoning.

Also, poisoning is a very risky form of suicide, high chance it will fail - you either don’t take enough and then survive the poisoning (maybe you vomit up the drugs while you’re unconscious, maybe a family member finds you and rushes you to the ER where they pump your stomach, etc.) - and often surviving a poisoning can leave you disabled, etc. You can survive a suicide attempt with a gun, I just think it’s less common if executed correctly.