Sunday answer

This is the receiver block from a MP-44 (STG-44).

The first picture are from “Collector Grade Publications” book “Sturmgewehr”. I highly recommend this book. If you are a student of weapons or military history this book is a must in your collection.

Here is a picture of the bolt in the machined receiver.

And as it starts to being retracted.

This picture shows the locking area of the machined receiver.

As always comments and Ideas are appreciated.