[TPM001]

I disagree with a GBBR as a superior sniper gun platform (unless you convert to an HPA rig). In my experience, there is too much variance in gas pressure to make your shots consistent. You may get the range (assuming your hop up is not contaminated with the oil in the gas), but you won't get the accuracy over AEG and definitely not over a bolt action springer.

If you want the ultimate sniper gun platform, go with a good bolt action springer (like Maruzen or TM) and properly upgrade it to the power and range you desire. When I say properly, I mean don't leave any weak spots. Don't just change the spring and leave everything else stock. Everything must be upgraded to the same spec simultaneously. Be prepared to shell out $$$ if you want the most accurate and long range.

And I wouldn't go so far to say that the size of the tightbore matters little. It matters quite a bit. If you go too big, you will lose your laminar flow and get turbulence instead. I would go with 6.03mm.