Go down to the local autoparts store and get some plain old axle bearing grease. Use it sparingly
in the operating rod channel. (applied into/along the channel surfaces with a Q-tip is fine), and in the opposite bearing channel inside the receiver itself.
There are some other areas while you're in there, so take as look at pics 1-5 here:
Again, not a glop... just a relatively thin smear.
What ammunition are you using?