The canon
Who sent The Thundrbolt the canon used to get into the bank vault?
shareIn Joe Millard's novelization of the film, he explains that the cannon came from black market underworld contacts that Thunderbolt knew from before through Billy Lamb, the mastermind of the first robbery.
shareAt last! A serious reply instead of some smarta** response! Thank you Jimmy19029.
shareYeah, except it's quite a stretch to obtain a 20mm anti-aircraft gun via an underworld contact than small arms. Something like that would generally involve a major arms dealer and artillery is going to cost a lot. It's a bit harder to make something like that disappear from an inventory. Even if you can get the canon, the ammunition is another matter and that ain't cheap either. They would need a much bigger bankroll than the film would indicate for that kind of hardware. Explosives would have been more believable.
Still a great movie, if you don't ponder that too much.
"Outside of a dog, a book is man's best friend. Inside of a dog, it's too dark to read."-Groucho
More info on the gun/cannon used in the film.
https://en.wikipedia.org/wiki/Oerlikon_20_mm_cannon
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I might as well thank you for your answer too as I was about to ask this exact same question. I think it bares mentioning that in the movie I got the distinct impression that not only were the non-Bridges characters ex-military, they were at least elite infantry soldiers of some kind.
shareEven now it would be, not easy but very possible to get that type of artillery but it would cost big dollars and as was mentioned, the shells would be nearly impossible to find so you would have to have them made, plus getting it around would be plain stupid hard. Still it might be easier to get the gun than it would be to get the equivalent explosives. A huge anti tank shell would also be more directional and effective... Who knows, I don't hear about people using military artillery to rob banks or really explosives either so I doubt this is really very practical. In reality you may get less cash from the robbery than the cost of the gun your leaving behind. It's a lot cooler than handing a teller a note though!
Don't count on hell ever running out of room
Nope, not as hard as you think. Even today, with several additional laws, there are a number of these sorts of things in private hands, etc.
As recently as the 1990s, you could easily get small quantities of live ammo that you totally should not have (up through 57 mm, bursting smoke and WP hand grenades, etc.), just sitting on tables at gun shows. Collectible stuff, that never /really/ gets used for nefarious purposes. These are very movie plot worries but they could be obtained.
Anyway, it takes place in the 70s. Even the GCA was very recently adopted, so there were warehouses of stuff that was suddenly harder to sell just sitting there, much of which got sent to other countries or disposed of. Back door deals would seem possible. Also, back then, the value of something like an autocannon was pretty low, really. It might have been quite cheap for their underworld contacts to get them, as no one else wanted stuff like that, and shipping would be the biggest issue.
Uh, no, not even close. You could find all kinds of small arms, maybe even grenades. Once you start talking about crew-served weapons, you are talking arms dealers, of which the US Government is the biggest. Those surpluses were generally sold overseas. I'd be willing to buy into a bazooka and a couple of rockets, maybe even a mortar (though not bigger than a 60 mm); but a 20 mm anti-aircraft cannon? Nope, no way. Not even in the 70s, which I lived through. Even in the hands of private collectors, you tended to find demilitarized (barrels sealed, firing pins removed, etc) weapons far more than working ones.
Now, had they showed them somehow breaking into a National Guard facility, I might have bought it.
Fortunately, Ah keep mah feathers numbered for just such an emergency!
I only said that because I have seen them. Touched them. Priced them at the time and noted how much I couldn't afford it even if I wanted it. I didn't even know it was illegal at the time, and know people who dumped stuff in the late 80s when they realized that it was super not allowed and there's no good amnesty so it's best to just get rid of it.
Secondhand, local museums get stuff donated from grandma's attic that is not demilled still. I mean artillery, not small arms. It's out there.
Agree it would have been simpler, and more fun to have a second (well, first) heist where they robbed an NG armory.