  The field dependences of the Labush parameter in nonmagnetic borocarbides are
measured by a method that does not require achieving a critical state. The
expected values of the critical current are estimated. The values obtained are
two order of magnitude greater than the results of "direct" measurements
performed on the basis of transport (magnetic) experiments. A giant peak
effect, which the collective pinning model describes quantitavely well, is
observed in the field dependences of the Labush parameter in Y-based
borocarbides.
