At the risk of hi-jacking the thread I'm trying to keep this to a bare minimum, but also try to help out with the comment on the Mosin Nagant trigger problem posted earlier. Squeeze & hold the trigger back, pull the bolt back / out of the gun, and then squeeze the trigger a few more times. It should move freely with about 1lb of "springy tension". If not, you need to pull the stock off and inspect the trigger mechanism for further damage (easier to do than shaking pee off the end of your willy). The two surfaces shown here (sear & hammer) are the ones under tension from the hammer spring, and would be the ones you'd want to square up & polish in order to fine tune your MN's "heavy trigger". You can take the bolt apart just by pulling on the two ends and turning one.
(pic is my M44 in the midst of being overhauled... Considering a full covering of Dura Coat Woodland Camo, milling off the bayonet lug & adding a scout scope...)
Hot tap water, & oven cleaner works
AWSOME for removing every last drop of Cosmoline. It's never harmed the bluing on any of my surplus guns either. Follow the instructions on the oven cleaner can (let it soak a few minutes).