Yes, you have to switch to single-shot mode and be crouching to get any accuracy with those. Most of the early weapons are rubbish but the later weapons are very nice indeed.
Ah! I was crouching and firing one at a time, but not in single shot mode, I'll give that a go!
You can change the difficulty at any time mate.
Cool thanks! Although I did get quite far yesterday, past most of the bits that were causing me trouble!