Firstly, edit your post and keep the bad language for other forums. A lot of kids read this forum and so it should be kept up to a high standard.should I ....... with r-hop if my field dmr limits are 450
Secondly, I may be able to help with your build.
A bore up kit does not really make a difference to cylinder volume. The increase is so minor that I would say it is pointless. So, what I am about to say is for a standard cylinder volume and you could still do the same with your rifle as the bore up kit is not really any different.
For 0.3-0.32gm bb's I use an inner barrel of 6.01x270mm. If you go longer you will find that the 0.32gm bb will be just traveling down the inner barrel on it's own energy. So the cylinder would have reached the end of it's cycle and the bb then has to continue through the rest of the inner barrel by itself. In my personal opinion, if you use a shorter barrel that matches the bb weight, I think that this makes the rifle more accurate and it can also help with range as you are getting the maximum energy out of the heavy bb.
Also, another big advantage to having a short inner barrel is that you can put on a long silencer and this can soak up a lot of the sound.
With the shorter inner barrel you will need a bigger spring and in turn a bigger motor. So the JG blue top (high torque) or the SHS is good. You may also want an 11.1v to run the bigger spring and with this bigger spring you should not get overspin.