Strange Police P-08

[SIGP2101]

Norme, do you referring to something like this?

Second pic looks exactly like attachment inside the barrel of that P-08. That is .22 adapter indeed. Other 4 objects on that picture I have no idea what they may be for. They do not look like 4mm adapter as John suggested. (first pic) Little dimples in the middle remind me more of lathe dead center tool used to machine those.