I'm guessing he did it legally.
I'm not really laughing over this one either.
Yep, banging out dents with a hammer is legal when repairing a silencer, even one made on an ATF form 1. Years ago when I made my first one, I had questions as to what parts I could repair or replace so I wrote a letter to the BATFE. The letter I got back was a bit ambiguous, but they said I could replace parts after destroying the wipes (rubber disks). I interpreted this is meaning I could only replace the wipes and no other parts. Others who read the letter said I could replace any other parts without paying another $200 tax. I have since read other letters saying that a form 1 silencer maker can not replace anything except wipes, so I am SOL on making those kinds of repairs. I can also not make any repairs that change the bore size or silencer length.
I hope the guys in the video were not laughing at the poor dude who had to pick up pieces of his can downrange. I have laughed at myself and with others who have experienced misfortune at the rifle range, but I have yet to laugh at anyone who had something come apart on them. As I have been known to be insensitive at times, that day may come when I do laugh at the wrong time and if it is like other times, then I will feel an inch tall soon after.
One time I was shooting a makarov over a chrony and one round did not record. I foolishly thought I shot too high and pulled the trigger again instead of checking the bore. The next round was blocked by the previous squib round and the pistol came part in my hand. After picking up the pieces from the ground and putting pressure on the hole in my thumb, I went to the range officer’s shack and asked for a band aid. Everyone was staring at me as I entered and asked for a band aid indicating my thumb. They asked what the hell happened to my face; I had blood streaming down my chin and did not notice it.
I got a few laughs after the bleeding stopped. They were the kind of laughs that a person gets when he receives crap from others about the dumb stuff he does. When a person gets crap for their injuries, they know they will be ok, then they get “Oh, you poor baby” talk, then it is time to worry.
Ranb