Mosin Nagant hints and tips. http://russian-mosin-nagant.com/mambo/index.php?option=com_frontpage&Itemid=1 Here are a couple of links that cover a couple of important and common issues with these rifles. Sticky bolt problem. http://russian-mosin-nagant.com/mambo/index.php?option=com_content&task=view&id=45&Itemid=59 Headspace information http://russian-mosin-nagant.com/mambo/index.php?option=com_content&task=view&id=44&Itemid=59 All about the MN family of rifles http://www.7.62x54R.net Another link with info: http://www.mosinnagant.net/USSR/mosin_nagant_markings.asp A couple of Youtube videos that show taking the bolt apart and putting it back together. The bolts are all basically the same so this will work with all Russian MN rifles. IMPORTANT The measurement he is checking is the firing pin protusion, NOT the headspace! [ame]http://www.youtube.com/watch?v=VE2QCCc6bz4[/ame] [ame]http://www.youtube.com/watch?v=PBQ9EVlaRmo&feature=related[/ame] Something to think about safety issues on the MN Rifles REMEMBER: The Mosin-Nagant HAS NO SAFETY GAS RELEASE PORTS. Unlike the Mauser K98, Springfield 1903, or Swiss K31, which all have safety ports for escaped gas from improper headpsace to run off in a "safe" direction, gas escaped from poorly headspaced Nagants have only one direction in which to go - your face. The Czar had plenty of conscripts and had no qualms about this. The firing pin has been known to come out of the rifle into the shooters face. Very rare, but do you want to take a chance with your eyes?