I have recently changed the strings on my guitar and have noticed that the bridge is flat with the body to as before from factory it was off the the body. I'm using the same gauge strings as from factory. Can someone tell me what's happened?

String gauges from different brands, even if the same gauge, can have different core sizes, and therefore higher or lower tension. All you gotta do is remove the rear cover plate, and loosen the 2 claw screws a touch, until your bridge sits about 1/8" from the top when tuned to pitch.

I always tighten the screws in the back down as far as I can. I hate having the bridge raised up off the body. But I don't use the whammy bar either so other players might not wanna do that.

You might want to recheck that you've got the right gauge strings. The CP 50's is shipped with 10's, unlike standard MIMs which are shipped with 9's...

Ok thats whats the problem, was told to use gauge 9's. If I was to change to 9's or 11's is it a matter of just tighting or loosoning the claw screws

Basically. String type and gauge will make a difference in the tension placed on your bridge. You can counter that by adjusting the screws in the back of the body.

Just to clarify (based on one of the replies), this is a two-point trem and I don't think you can make is flush against the body like you can the traditional 6 screw trem (the fulcrum points are higher).
It's VERY good at staying in tune however.
And yes it did come with 10's

I have a Classic Player '50's Strat and I WAS able to get mine down flush with the body. So it's certainly possible.

Cheers for the info guys, Got some ernie ball gauge 10's went on well execpt the High E String, it snapped as i didn't leave enough string when going in to the machine head. I have contacted my local guitar shop for a single 10 gauge string but they only do D'Addario strings. is it ok to mix the makes of strings if its the same gauge to match the others?

Go for it. It won't hurt anything.