When I see the rating for a bullet like a 9 mm Gold Dot
https://www.luckygunner.com/9mm-147-grain-jhp-speer-gold-dot-le-50-rounds
“320 Foot Pounds”
well, that means it does about as much work as someone lifting 640 pounds, half a foot.
And I can’t help but wonder - how does that compare to the piston on a car engine when the gasoline ignites/ explodes ?
I was hoping that some of the forum members might be knowledgeable about Cars.
Of course, there is a Method to this Madness.
I’m not just asking random questions about cars, on a gun website, for fun. 
I am interested in using Nitroglycerine and/or Nitrocellulose - Smokeless Powder in other words - to power an Internal combustion engine.
From working in Silicon Valley - I started in the Wireless industry in 1980 - I know that you have to plan realistically about Design Iterations.
Having Gasoline in a tank is one thing. Having a Gas Tank full of Nitroglycerine and/or Nitrocellulose - well that sounds like the “Bang Bang” part of Chitty Chitty Bang Bang (old movie).
If I was working in a corporation with an R&D schedule, to deal with the safety issue, I would be packaging the fuel in 9 mm brass. And “firing” the hot gas when the primer gets struck by the firing pin, into the cylinder, to push the piston. (My firearms background is more rifles & semi-auto’s, so if it has a striker instead of a firing pin, that works too.)
Why 9 mm brass ? Because there’s so much of it. I collect brass and have a little 38 Special, a lot of 45 ACP, hundreds of S&W 40 … and about a 100 pounds of 9 mm brass.
So basically the car engine would be mostly automobile, with a little bit of semi-auto.
If it were done right, it would be very cool. It would have a Cool Sound.
Eventually the novelty of a fuel tank with 1000 rounds of 9 mm blanks, and a storage area for all the empties, and the fact that it can only go 20 miles on those 1000 rounds … well yes eventually there would be a meeting in the engineering department where people would say, “We have to find a better way”.
But the way it works in design is, you have to build the first one before you can build the second one. The first one gives you something to criticize.
The main thing is, it has to be Safe, and Useful. It’s TBD what the mileage would be.
I trust that Smokeless Powder is just as economical in the long run as Gasoline, so the trick is learning to store it safely, when used as an Automotive Fuel.
Well, I know one way to store it safely. Magazines of 9 mm blanks. Big Magazines.
It does sound kind of Mad Magazine-ish, I admit.
So the question is - what force does a car engine push on the piston with, when the gas explodes in the piston ?
Is it about 640 pounds ? Does it push the piston about 6 inches ?
If so, it just did 320 foot pounds worth of work - same as a Speer Gold Dot 9 mm.
