Yeah, I was talking to a guy in Korea and he said the same thing about .2J, but he also said that nobody follows it.
I think a good bit of it is likely just target shooting, but I imagine that there are some pretty hardcore games.
Apparently the Philippines, Taiwan, and Indonesia have the craziest stuff, with most everybody I see in Taiwanese gameplay vids rocking GBBRs and AEGs sling .40g ammo at 2.5J as a primary. I imagine CQB is different a lot of the time, but that is a bit high even just from a role standpoint. You don't see much or really any bare skin on those guys though, even in drippy 100* weather.
@Lds What exactly do you need help with?