Thank you very much, I plan in dealing a groove in the screw and I'll glue in a driver bit. See if I can get it out.
I'm aware of a few issues with the we mp7 as a few friends have them. The bolts holding the nozzle in are slightly different on theres. I could simply have a lemon.
Currently I'm sitting at about 360-365 fps using ASG ultrair. The npas was cheap at 16 quid so I thought its worth a go. If the consistency isn't there I'll look at other options, maybe make the nozzle adjustable. I know that's very popular on GHKs.
I dont fancy making the barrel smaller as I do plan on running the angry gun mp7 silencer with tracer unit built in but we can always see.
Thanks for all the help. I'll have a look at all the recommended links once I'm finished work! Cheers buddy