Abstract: The unstable behavior of generally accepted strength characteristics of a material makes it difficult to evaluate the dynamic strength of a material in high-speed loading problems. This work reveals a new effect, which in a number of practically important cases of tests with a controlled loading rate for evaluating the dynamic strength allows us to offer a convenient time characteristic of the incubation processes of failure under high speed loads. It is shown that this time characteristic does not depend on the strain rate or loading rate and can be determined from general experiments. This makes it possible to enter a material parameter that can be used for criteria for evaluating the strength of a material under high-speed loads, including for calculating the rate and time dependence of critical failure stresses.