Mosin Speculation .

[Railcar]

Pneumatic (air powered) cutters for light gauge metal. they are sometimes called air nibblers, put a hole in the metal big enough for the foot, and you can zip around the entire can in no time.

http://www.factoryauthorizedoutlet....y-duty-18-gauge-3-200-strokes-min-air-nibbler

 

[jersurf101]

I work in a professional kitchen and a industrial can opener makes short work of spam cans.

 

[MEATSAW]

I got lucky with the first spam can I bought as it came with the can opener. I've kept it ever since.

 

[LED]

Railcar -thank you.
I don't open that kind of spam often enough to invest in pneumatic shears.
Jersurf - can you describe the industrial opener?