Pulse propagation and shaping are investigated in photorefractive self-pumped phase conjugators in both transmission-and reflection-grating regimes. The dispersion properties of self-pumped phase conjugators are analyzed by taking into account both the grating dispersion and the angular dispersion. The complex transfer functions are obtained by treating the crystal as a linear dispersive medium. We show that the pulse width as a result of the self-pumped phase conjugation is much wider in the reflection regime than in the transmission regime. The experimental results are consistent with the results calculated for the transmission-grating regime, indicating that this type grating is the dominant mechanism in the case of a femtosecond self-pumped phase conjugator.