Quote Originally Posted by BuffCyclist View Post
Just out of curiosity, how did you find that? Were there malfunctions associated with it or were you simply deep cleaning?

I only ask because I don't recall the last time I've taken my BCG apart for a real cleaning... I did it the first few times, then got lazy and now my rifle just gets a bore snake a few times, BCG sprayed with CLP, shooting range, wipe off outer dust and back in the safe.
Gas rings are considered a consumable item. When they lose tension they are sacked and should be replaced. A quick test will tell: extend the bolt in the carrier and set it on a hard surface boltface down. If the rings have sufficient tension the bolt will hold the carrier up in the extended position. If it drops, replace the rings.
The carrier/bolt will get crusty and fouled. You need to keep it relatively clean. I always coat the carrier and backside of the bolt with Tetra or a similar SYNTHETIC oil. It helps to keep the carbon from sticking as badly.
Hell, I have worked on a couple of them that were so bad I had to soak them overnight in Berrymans carb cleaner overnight.
Some "Smiths" and owners insist on polishing the back of the bolt thinking it will prevent carbon from sticking. Wrong, it is still going to stick and now you have taken off the parkerizing which is essential for corrosion resistance.
If Eugene Stoner would have thought it best to polish it he would have designed it that way.