TL:DR “Not invented here” After NATO was formed in 1949 it was decided it would beneficial to standardise small arms calibres. The British offered a . read more
By all reports the 6.8spc, and a similar round the 6.5 grendel, are nearly ideal for an asault rifle. Both have significantly lower recoil then the 7.62 nato, and are more controlable; but they have superior ballistic (both external and terminal) performance to the 5.56 in all areas (and in fact sometimes superior performance to the 7.62). read more