Need new barrel for Famae SG 540-1 5.56

[CobraGT]

Could someone explain to me how the core of a bullet affects barrel wear.

Math and science and stuff. I don't understand it either.

 

[r34skyline]

Could someone explain to me how the core of a bullet affects barrel wear.

Not necessarily the core. It's the bimetallic jacket. It doesn't deform as easily as the soft copper jacket nor does it have comparable lubricity. This generates heat. And the friction generates heat which causes the accelerated wear of the barrel.