High time-resolution measurements of trapped and precipitated >30-keV electrons from the low-altitude polar-orbiting satellite Ogo 6 in the postmidnight-to-dayside region of the auroral zone are presented. It is found that precipitation usually occurs in brief bursts of a few seconds duration or less, with normally a very abrupt transition between no precipitation and isotropic (full loss cone) precipitation. Thus if pitch angle scattering is the precipitation mechanism, it seems to be either very strong or nearly nonexistent, and intermediate-strength pitch angle scattering modes do not usually seem to represent a stable precipitation regime in this part of the auroral zone. Sustained precipitation in time and/or space is found only at very high flux levels, whilst the duration as well as the frequency of the burstlike precipitation events observed at lower flux levels apparently decreases with decreasing flux of trapped electrons. This is consistent with theories which predict the existence of a critical flux level at which the electron population becomes unstable and strong pitch angle scattering takes place, though there remains the question of how the burstlike precipitation is generated. The action of a delayed negative feedback mechanism is suggested. The burstlike character of the precipitation is of great importance for the average lifetime of electrons drifting in the geomagnetic field, as it reduces the average loss rate to a level which obviates the need for any additional acceleration in the morning-to-dayside region to explain the ability of such electrons to gradient drift most of the way around the auroral zone.