With the AWB expiring in less than 9 months, I'm thinking twice before buying a post-ban CAR stock.  Can I buy a pre-ban collapsible and pin it myself and remove the pin on 9/16?  If that's legal, how do I do it?

Come on guys, somebody gotta know.  

The only solution would be to blind pin in a way that would not be easily removable, and then submit the sample to BATF for approval.

The only way that I could see you even trying to accomplish the task is to start with an aluminum butt stock, then blind pin and weld the hole pin hole closed. Blind pinning on a fiberlite stock and using JB weld to close the hole has not been allowed.

I remember reading about people un-pin their post ban CAR stock, adjust it to a desirable length then re-pin it.  You mean that's illegal?

MOST, post-ban Non collapsing CAR stocks are a full length buffer tube and you couldn't break "the pin" and make them shorter.  With these stocks the plastic stock is glued to the end of a CAR shaped full length buffer and short of cutting the stock off, shortening the buffer tube, welding a new cap on the buffer tube, replacing the buffer and buffer spring for CAR units (post-ban stocks come with rifle buffers and springs), and then you may need to mill new catches into the shortened buffer tube....  well, I just don't see people as being likely to want to do that much work to convert a $50 used item!

In answer to the question, you need to decide for yourself on what a "folding stock" is...  The BATFE has said that a collapsing stock is a folding stock BUT there is no guidance beyond that as to what is needed to make it "non-folding".

With AKMS (AK-47 folding stocks) guys use a simple tac weld that could be easily ground off and the stock refinished later if the law dies without replacement so I assume you could apply the same logic to the AR-15 CAR stock.  The problem with the plastic stock is there is no easy way to weld her in a specific position.  You might try eppoxy as your liability is much less then a manufacturer who needed to make sure a person couln't easily modify their stock to an illegal form.

You might be able to do it with a metal stock as well but I am not sure it is worth the effort at this time.  If you did, I would argue that the tac weld could be adequate as this is how other weapons get around the issue.

Personally, I would look for a cheap used Post-Ban CAR stock or use what you have until you see what the bill does.  You may want to have a CAR stock in the safe at home, however, just in case the Crime Bill sunsets for a brief period before some new law comes into effect.

Good Luck!
QB

Thank you Quarterbore and have a Happy New Year.