UTony,
* 8,82 = 8.82mm which is the actual bore diameter measured land to opposing land when new.
* The "Centering Line" is likely the barrel to receiver "witness" mark. You can do a search on this term to find a generous thread discussing this mark and its implications.
* The letters C, O, J, & L are thought to be DWM worker acceptance stamps for various tasks they were assigned.
* Hope this helps.
* 8,82 = 8.82mm which is the actual bore diameter measured land to opposing land when new.
* The "Centering Line" is likely the barrel to receiver "witness" mark. You can do a search on this term to find a generous thread discussing this mark and its implications.
* The letters C, O, J, & L are thought to be DWM worker acceptance stamps for various tasks they were assigned.
* Hope this helps.