from my experience with the G3 in other games...
it's supposed to be a close-mid range battle rifle
it's damage is devastating due to its 7mm bullets
You're pretty much wrong on both counts.
It's a german 7.62x51 NATO battle rifle that is supposed to be an all-around rifle, although it's less than ideal for close combat because it's as uncontrollable as forget in fully-automatic mode and even in semi-automatic mode multiple accurate shots are hard to make due to the excessive recoil.
The 7.62x51 is a more powerful round (it's a full sized rifle round compared to intermediate cartridges, such as the ones used in the M16) than those used in assault rifles. The bullet itself is closer to 8mm than 7mm, and the power mostly comes from the incredible velocity the bullet is propelled at rather than how large the bullet is. Take for example the 7.62x39 Russian intermediate round, used in the AK-47. This round is less powerful than the 7.62x51 NATO because it is shorter and the cartridge itself holds less power, meaning it is propelled at a slower speed than the 7.62x51 NATO, and that means more often than not the 7.62x51 NATO will have more entry and stopping power.
Both will kill you pretty good though. Except M43 7.62x39, they're not exactly the best.
