At low temperatures,gun propellant grains may become brittle and this can lead to fracture or shatter of the grains during gun firing.Should this event occur then it will result in an increase in the burning surface of the propellant and will give rise to a change in ballistic performance.Also,if the resultant over pressure is sufficient,a breech failure may result.Understanding the propensity of a grain to fracture or shatter is therefore important in determining its safety in use.This document describes a test that may be used to derive knowledge and to quantify the physical behaviour of a gun propellant grain at the low temperatures at which fracture or shatter is most likely to occur. At low temperatures, gun propellant grains may become brittle and this can lead to fracture or shatter of the grains during gun firing. So that this event occurs then it will result in an increase in the burning surface of the propellant and will give rise to a change in ballistic performance. Also, if the resultant over pressure is sufficient, a breech failure may result. Understanding the propensity of a grain to fracture or shatter is therefore important in determining its safety in use.This document describes a test that may be used to derive knowledge and to quantify the physical behavior of a gun propellant grain at the low temperatures at which fracture or shatter is most likely to occur.