H3 Bursting charge

Composition

25  
Charcoal (Hemp or Paulownia)
2  
SGRS

Description

This energetic burst charge is used for small diameter shells (2...3 inch), since it makes a large and symmetrical burst possible. Besides the composition below, a ratio of chlorate to hemp coal of 10:3 is also popular. The sensitivity of this mixture to shock and friction is unexpectedly low, as long as the composition does not come into contact with sulfur or sulfur compounds

Source: 
Shimizu[1]. Page 207