Really scary and interesting, especially as I have an Air Ranger myself . . .
The one that blew has something different than mine does, and also different than the picture from bigmike of a factory one in the second post too - if you look you will see that the aluminum bottle has some form of "collar" on it that spaced it off of the action about 15mm or so. I don't know why, as it clearly is too small to be a regulator or anything like that, and you can see in the photo that the failure occurred inside this "space" as well. On mine the threads engage the full length of the bottle, which are M18x1.5 with about 20mm or more of engagement - this set up reduced that engagement by a lot.
I believe something is not "factory" about this gun, and of course we do not know the pressure it was run at. But the bottle did not fail, the interfacing part on the gun failed, most likely because it was not being used as designed . . . . clearly more info will surface on this one . . .