Thank you. Can you point me at a good reference site or book. I spent most of last evening checking sites and came up dry. I pulled the handguards off and found inside of the handguards marked with SL over N over 74. Is what I am thinking is a weird looking AK mark the Maltby mark? I fired the rifle this morning after reading Badger's information about headspace. I was using SA PMP. After firing I compared the five expended cartridge casings to some of the original, loaded rounds and could see no deformities at all of the brass, just some change in the color of the brass due probably to the heat. I will get the mic out later and see if there was any stretching but I can't see any by just looking. I appreciate all the help here. If someone is looking for a #4Mk1 I would recommend these based on what I received. I did note that I had the camera set to B&W and will try to post some more pics after a while. Should turn out nice as we have some sun finally here in Kansas.