Originally posted by: nathan
If you have cosmolene inside the bolt, just wrap it with tin foil and place it over your bbq grill for 20 mins. Makes sure temp is really hot about 500 degree F. Remove from grill and you can see melted cosmolene oozing out of the firing pin channel. Let it cool and wipe dry. Test for FP for freefloat by shaking the bolt. Easy...
I'm no metallurgical expert, but that sounds like a really bad idea to me.
I don't know if 500 degrees would be enough to negatively affect the temper of an SKS bolt, but I do know that some steels are annealed at temperatures well under 500° Fahrenheit, so why take any chances?
Barbeque grills aren't near as precise and controllable as annealing ovens, what you think is 500 degrees might be considerably hotter and could lead to a catastrophic bolt failure with your face just inches away from 45,000 pounds per square inch of pressure.
Totally aside from the possible tempering issues, greases, soaps and related petrochemical products usually turn to carbon if heated too much, and baked on carbon is a lot harder to remove than any grease or Cosmoline.
Just take your bolt apart, remove the firing pin and extracter carefully and then spray everything down with Goo Gone or Goof Off citrus cleaner.
Give the solvent a couple of minutes to work, then scrub everything down with a toothbrush, a worn out bore brush and some Q-tips or pipe cleaners.
After the solvent and scrubbing have removed all the crud, scrub your cleaning tools with some Dawn dishwashing detergent and use them to have at the bolt and it's related parts again with Dawn and hot water till you've got the solvent removed and everything is down to clean bare metal.
While doing all this, keep a sharp eye out for small pieces of debris such as steel or brass shavings from cartridge cases and brass "plugs" from pierced or "popped" primers. Debris of this nature can cause your firing pin to stick, which can cause your weapon to slamfire (possibly even a "full auto" mag dump) when you drop the bolt.
Conversely, the extra friction might also cause your weapon to misfire when you pull the trigger.
After disassembly and cleaning, use compressed air to blow any leftover water out of the recesses of the bolt and then finish off by heating the bolt and it's parts for a couple of minutes with a blow dryer to ensure that everything is bone dry and warm enough to assist in coating things with a light, even layer of good quality, non gumming oil (I like Mobil1 5w20).
Once you've got the metal protected, carefully examine the parts for damage. Look for a worn extractor (you can Google for pics of both good and worn out extractors), a weak extractor spring, and also ensure that the tip of your firing pin is well rounded, with no pitting or other deformation.
You should also look for shiny wear spots on the firing pin and within it's channel, since these can be indicators of a bent firing pin.
Doing a proper disassembly and cleaning of your bolt may not be the easiest way to rid it of Cosmoline, but it's the safest and most effective way. "Cooking" your bolt or paying someone else to dunk your rifle in a solvent bath isn't going to remove solid pieces of debris from inside your bolt or reveal a bent firing pin.
Disassembly will also help you learn more about how your rifle works and assist you in making any needed repairs in the future.