***Warning! Do NOT try this at home!***
I noticed a couple of propane bottles I have kicking around my place have this problem. I swap bottles around for lots of stuff so I just put them in the shop to use instead of with my airsoft gear.
I was curious though, what would happen if you put the adapter onto a problematic bottle and lit it. I did this out in the yard. HUGE ass flame came out (of course) so I rolled the bottle down the road where it took off like a rocket back towards my yard. It nailed my fence and destroyed a good chunk of it as the bottle exploded. Now I say again, DO NOT TRY THIS AT HOME! I did this for a test and because I like blowing stuff up. I apologize in advance as I didn't think to video the fun. The propane adapter came through absolutely unscathed.
One more time, DO NOT TRY THIS YOURSELF. I had LOTS of personal protective equipment, firefighting gear and other safety equipment, as well as experience with this stuff. If you like your fingers, play safe.
"Anyone with a name like Amanishourbariki should give a few letters to the poor Ng family." - Snarfangel, Fark.com