Denix Coach Gun APS Shell Conversion

[robzz2012]

I’m incredibly keen on the idea of being able to convert this to operate with APS shells (not interested in PPS et al). 
 

If anyone has definitive knowledge/reference(s) on how to achieve this, I’d be most grateful. 
 

View attachment 147484

 

[BigStew]

Its for plug fire but the principle is the same https://sidewinderforge.co.uk/netsinc/No2p23.html