Expressions I might need revising
1. In Western films before this era, when a character was shot, they would just place their hand on it and collapse.

2. At the end, they are machine-gunned to the death with 160 bullets.

3. This was actually the first film in the history of cinema that ever showed blood when a character was shot.

It would be great if you could give some corrections.

Question

Expressions I might need revising
1. In Western films before this era, when a character was shot, they would just place their hand on it and collapse.

2. At the end, they are machine-gunned to the death with 160 bullets.

3. This was actually the first film in the history of cinema that ever showed blood when a character was shot.

It would be great if you could give some corrections.

Answer

1. They would just place their hand on what?
The (gun-shot) wound.

(...) they would just place their hand on their wound BEFORE they collapsED.

2. Machine-gunned to death.

You can leave 'the' out.

The rest of the text is correct. :) My advice is to make this post an entry on ITalki instead of a question. That way I can mark, correct, comment and change things in your text easily.