Mark Walton is mostly right - but not completely.
Wait until the gunner reloads and then run nearer and hide. Then when you are close enough you can pop from behind cover and do head shots. It would be a shame to rush through the game - spend some time enjoying the beautifully visualised and detailed environment. The music adds much to the atmosphere too. Definitely the best of the CoJ series. The writers have the auto-save function right, not too close, not too far apart. The face to face combat mechanism has been greatly improved. Worthy enough to replay.
My credentials? Gamer since Spectrum came out.
You've read what Mark wrote?
I've added a secondment and corrected his error, any further writing is purely to meet the 800 character minimum. I prefer precision rather than meanderings.