A fully tuned MP7 with an external battery rig and a longer barrel under a silencer can begin to think of getting outdoors fps.
However, you need to start with a TM base and drop hundreds in the project, to end up with a thousand dollar glorified pistol.
Also, I wouldn't advise doing this with a clone.
Since you are not verified the TM is out of your reach.
Look for something else or get verified.