Specific impulse of military missile !?

Anyone with information about the Specific impulse of the missile engine used in the military?

The performance characteristics of a specific propellant is called the specific impulse of the propellant (solid-fuel) or specific thrust of the propellant (liquid-fuel). The specific impulse is a measure of the “quality” or “merit” of the fuel and is defined as:

Isp = Tavtb = It

mpg mpg (17-2)

where

Isp is specific impulse (sec)

mp is mass of solid propellant (kg)

g is the force of gravity (9.8 M/sec2)

Although the units of specific impulse are seconds, the Isp of a fuel is actually the amount of impulse per kg of fuel. In other words it reflects the specific energy of the fuel. Thus, the fuel with the highest Isp will produce the greatest performance.

Propellants are classified as either solid propellants or liquid propellants. Nearly all of the rocket-powered weapons in use by the United States use solid propellants. Liquid propellants are still used in some of the older ICBMS and will be used in future cruise missiles. Of course, all thermal jet engines burn a liquid fuel.
http://fas.org/man/dod-101/navy/docs/fun/part16.htm

Et:
Kh-31 families (Kh-31A/P…)

31ДП engine has maximal thrust ratio of 0.8 and specific impulse in 1300 kgf/kg sec at Mach 2.5 at the altitude 10 km.
It’s installed on Kh-31 “air-to-ground” cruise missile.
http://www.tmkb-soyuz.ru/91