About 3-4 years ago I did a test using an obsolete accounting textbook. The book was hardcover, had many pages (guess around 1,000) and dense paper. I fired my Walther P-38 into it using 115 grain FMJ 9 MM and my Pietta 1860 Colt Army using light loads at around 35 feet. The Army's 44 caliber ball penetrated one third of the book, and the P-38 did about two thirds penetration.
I was surprised as the P-38 is no hunting magnum revolver with it's 4" barrel, I thought the Colt would do better being a .44.
In 1989 I did another experiment using a Euroarms 1851 Colt in .36 ball and medium loads and a Mauser Broom handle pistol with a 5" barrel and using 7.62 X 25 Tokarev surplus ammo FMJ, I think it was Yugoslavian. The target was an unwanted steel WOK pan, range was probably around 30 feet. The Colt Navy only dented the pan, shallow dents at that. The Broom Handle went through it like warm butter. I later learned that the 7.62 X 25 Tokarev is noted for heavy penetration, even through an automobile.
I was fortunate that I could do these tests at locations where I could setup items to be test penetrated, most ranges won't allow people to do this. And I was nervous about ricochets from the .36 caliber on a rounded steel item.
In another test I used an old nickel plated revolver, one of those junky .38 caliber Saturday night specials that did not work, I think it was an Ethan Allan, or a branch producer. I hit it twice with my Beretta 92 in 9 MM using 115 Gr. FMJ bullets. The grip got knocked off and a shallow dent in the frame. I then used my Remington 700 in .243 on it, range was around 50 feet for both. I hit it twice with the .243 ( I don't remember the bullet weight), One round carved through the cylinder like warm butter, and the next blew the gun in half like it was glass. I really respect center fire rifles after that.
