A: The end of my barrel is covered in this short free floating rail and i have no idea how to get it off there since i have my gun wired to a peq box. (what i mean is i have a wire running through my guns hand guard)
B: I have this little nub in the place of my stock and it appears to have no pin or screws or anything to take it off..It is immensely frustrating.
Anyone who can help me with this? I would be really grateful.

Edit: Sorry if this is stupid to ask but i just received this gun a week ago.
Pics!!: http://i42.tinypic.com/2ilk1vc.jpg
stock: http://i42.tinypic.com/15gtbv5.jpg
possible pin?: http://i44.tinypic.com/begavn.jpg
top of rail: http://i41.tinypic.com/2nkighv.jpg
bottom of rail: http://i41.tinypic.com/15ecl7q.jpg