g&g g96 Question

[Toan]

so a buddy of mine has the g&g g96 gas sniper rifle and he wanted to upgrade the inner barrel. and so far hes found 2 barrels that he was looking to buy. hes not too sure if he should get a 6.04 tbb or a 6.01 tbb. also he was wondering at that length (655mm) would the 2 different sizes of inner barrels be any different from each other? below is the link of the one he wants to get but he wasnt too sure if he should buy the edgi one on airsoft gi thats a 6.01.

http://www.airsoftoutletnw.com/index.ph ... niper.html

http://www.airsoftgi.com/product_info.p ... ts_id=7001