Okay, I have no images so I must be very descriptive.  First I have a Model-1 upper in 7.62x39 and a EagleArms Lower.  I have had 2 problems with the buffer retaining pin.  First, when I first put the kit together, I did not know if I should submerge the buffer retaining pin (BRP) below the CAR stock tube or just butt it up against the tube and really tighten the tube ring.  Well I decided to submerge it.  Bad idea.  The pin was slightly sheered and bent forward.  I then tried to set the pin to butt up against the CAR stock tube but after 20 rounds, it popped out while firing.  Now I have a BRP on order and my fingers crossed that the new pin will stay in place during fire.

Is this right?  Have you had any thing like this happen?  Thanks for you help.

Yeah, you got it right the second time.
The buffer tube butts up to (not on top of) the BRP.
Luckily it is a cheap fix, and once the pin is replaced you should have no more problems.

Just press the retaining pin down, spin the receiver extension to just kiss the center post, and then back off the receiver extension to index it with the receiver and tighten the retaining nut.  

Also, on a few of the clone type butt stocks, the front of the tube needs to be shorted by a hair.  When you back off the receiver extension to index, make sure that the tube is at least covering 1/2 or more of the lower edge/lip.  If it doesn't then you will need to shorten the tube end to allow it to be screwed one more turn in to index the butt stock, yet not press up against the center post.