you can often tell if a receiver has been rehardened, if the action binds and the triggers and safety do not operate smoothly. this is due to the receiver metal being warped, which is often an unintended result of the re heat treating process...

in severe cases, you may actually see cracks in the receiver metal caused by the stress of the re heat treating process.

better not to mess with the original receiver heat treating as done by the manufacturer.

Last edited by ed good; 08/18/13 09:22 PM.
keep it simple and keep it safe...