A typical bullet? No. However, tracer rounds are highly visible. On a clear night, you can watch satellites pass over and those travel at speeds ranging from ~7,000 MPH to 18,000 MPH (depending on their orbit altitude).
yes, you can see tracers as well as a .45 round depending on where you are standing. the human eye can pick up very fast moving objects, it just depends on where you are standing and how far away you are from it. can you see a shooting star? can you see the sun rise every morning? these are things that are happening at very fast speeds, yet we can still see it because of where we are in relation to the moving object.