I apologize Alan and Matt,
I dont think i made myself clear on this one.
I fully understand about the clamping force reducing the id of the outer bearing race, which it would to a certain degree.
I could not put enough force behind my hex driver so i have used a ratchet handle and hex bit to tighten down the bolt to the point where the alloy around the bolt has distorted, i can even see the distortion from the top of the swash.
I was not happy putting that much force on an m3 bolt in alloy.
There is still some play in there and the bearing has spring back now.
also, i have never had a new heli develop that much slop in the swash after just 25-30 flights so i think the bearing has failed for some reason.
Thanks for your support guys,
Chris.