Is science too much about assumptions?

[BMaker11]

archer9234 said:

d21lewis said:
I was told that the only reason bullets go in straight lines is because you were told that's how they move. Truth is, you can curve a bullet. I saw a documentary where a guy curved a bullet and shot like four or five different people standing in a circle.

Was the bullet altered in any way? Because Mythbsuters tested this a ton of times. And they never got  it to curve.