The ‘loss’ of m855 is nothing to many of us.
Round here, aside from being overpriced blaster ammo, all it is is a source for cases.
Its main reason for desire, that mild AP capability, actually makes it less desirable. Especially when compared to s 40-45gr SP for home defense or a good 60+gr hunting bullet for everything else. The Barnes 70gr TSX for example has taken the .223 from a poodle shooter into the realm of a serious hunting gun.
Don’t have AP, no big deal, aim for the joints and soft parts, you’ll have better effect anyways.