Special Weapons And Plastic (SWAP) shows you how to take apart the lower receiver of the WE Airsoft M4A1 GBB... "Today I will disassemble the lower on my Wei-Tech M4A1. So I can let loose my destructive behaviour, in a controlled environment. The only parts I won't disassemble down to the bare bones are the stock and the trigger guard, since it is better to just buy the entire assembly if you want or need new ones.

And the trigger group will be covered in a separate video since it is an intricate and complex part, in and of itself."

Read more here.