Somewhere between a short sharp stick and a 105MM howitzer round.
"How lethal" is a simple question which doesn’t have a simple answer.
There are too many variables to answer that question as written.
Who is getting shot?
Where in their body are they shot?
From how far away?
What was the position of their body as the bullet hit?
What is their overall physical condition as they are shot?
What is their mindset when they are shot?
What is the temperature of the location they are shot?
What clothing was being worn as they were shot?
What bullet was used?
These are a few of the questions that must be answered before such a question can be considered, and I am sure I have missed a few too.