Is this possible...When you use that Black Box like Tool to remove a Rear Sight and the Sight is Not budging even when you oiled it overnight can the Receiver start to bend inwards from the bottom when your applying more strength ? I have a friend who insists on Breaking down his Carbine and trying to fix something when he doesn't know much about it, but can Shoot and hold his own against us old Grunts (at Short distances) brought it over and ask me to pull back the Slide and Cycle it and that's when he told me he was changing out his Rear Sight and felt something different. Well right when the Bolt was starting to move towards the dovetail it felt Tight nothing like I've felt before. That's what I was looking through my Books just to see if there was something about that happening. Now that I exhausted what and where I would look to find Answers I didn't, so now I'm asking if anyone thinks it can happen and what can you do about it. One thing I know for Sure now is that I will not loan him any of my Carbines anymore when he goes Shooting with his friends.