My first impression was that it was actually computer-translated from English, judging from the spelling of some words.
Yes, probably. It's a very poor translation. The text is a total mess. It is grammatically incorrect. And I hardly understand it.
Usually computer translations from English to Russian are better. So the source might be non-English.

Does "Маузер" mean "Мао Цзэдун"?
No. I don't believe a computer translator could translate Mao Zedong as Зигфрид Маузер.

А "Маузер" - это, конечно, пистолет.
No. «Зигфрид Маузер» is not a gun. The gun developer's name was Peter Paul, not Siegfried.

Зигфрид Маузер is Siegfried Mauser, the German name. Wikipedia knows only one Siegfried Mauser, the German pianist: Siegfried Mauser - Wikipedia, the free encyclopedia
I don't think the text is about him