Diaphragm Shell.
Image: © 2000 Aeragon; all rights reserved.
The basic Shrapnel design shell underwent several modifications and improvements. The diaphragm shell was developed by Colonel Boxer of England’s Royal Artillery Corps as an improvement to the original Shrapnel design shell. His modifications to the design improved manufacturing and bursting characteristics of the shell. The diaphragm shell incorporated a metal diaphragm that separated the explosive charge from the shot and included weakening grooves in the shell thereby improving its bursting characteristics.
Diaphragm Shell.
Image: © 2020 Aeragon; all rights reserved.