Case head separations caused by very high pressures stretching the case, are VERY different to case head separations in low pressure cartridges fired in double rifles.
Double rifles are a totally different ball game in that respect.
What I'am saying is that separations can occur in DR's due to TOTALLY different reasons to what happens when "Harry the Handloader" overcooks the load for his bolt action super-boomer, or overworks the brass with a badly adjusted resizing die.
To fully understand the difference, you need to have done a LOT of double rifle shooting and a LOT of double rifle reloading, particularly with bottleneck DR cartridges.