The spin wave excitations emerging from the helically modulated ferrochiral triangular magnetic order in Ba$_3$NbFe$_3$Si$_2$O$_{14}$ were investigated by neutron scattering on a structurally enantiopure single crystal. The collected spectra are accounted for in the minimal model explaining the magnetic order and its total chirality. It is found out that the spin waves excitations emerging from this order display remarkable properties: (i) spectral asymmetries answerable to the structural chirality and (ii) spin correlations evidencing full chirality of the spin dynamics over the whole energy spectrum.