bolt action versus aeg

I'm looking into making a project. My goal is to have an accurate replica that has a longer range than a normal aeg (echo 1/combat machine) and has the accuracy to take out people at the extended range consistently. My questions;
does the accuracy of a bolt action replica transfer over from real steel counterparts (never did learn that)
what's the most effective tbb diameter, while still not jamming after five shots
what is the best fps for range, does the echo 1 m28's 550 fps work better than an upgraded 400 fps replica
finally, should I just stop while I'm ahead and get some asgi upgraded l96/g4 dmr?

I'm pretty sure that bolt action vs. normal gearbox doesn't really make a difference for accuracy in airsoft. I found that a 6.03mm tb was perfect for accuracy and mine never jammed on me. I got 100 yrds consistent accuracy from my old l96 with about 530 fps.

As a little anecdote, I've seen MP5s more accurate than M16s, and two L96s that were the same brand and both stock, yet one inexplicably shot better than the other. But to answer your question, no, it does not transfer from real-steel.

I never really noticed a difference between 6.01 and 6.03, although I've heard that 6.03 is fine). Also, I've heard that after 420mm you don't really get that much of an accuracy boost unless you use a bore-up kit and bump up your FPS (since the BB just bounces around the barrel after that.

Not sure, as I primarily run assault rifles. I always did want to try sniping....

I know those DMRs GI has are amazing, since they have a preinstalled 6.03 TBB and because I owned a couple G4s a while back. I've also heard that their G700 and G96 rifles are really nice for the price you're getting them.

6.03 FTW! 6.01's are a little more accurate, but aren't worth it because of all the jams that you get. The 6.03 in my m16 was a beauty, hardly ever jammed, and got great results. bR55 Pretty much said it about GI customs, they rock, although they're quite pricey. Good luck!