Original U.S. Vietnam War Empty / Inert Composition C-4 Block MG 42 Bolt & Barrel Assembly The original marking looks to

The original marking looks to be O A I M K 1

Targets included U-boat installations at Kiel

Guy passed away in 2010 and a link to his obituary can be found at this link

Clearly the real effort was the carefully prepared chain of charges that allowed the shooter to discharge the front load first and then automatically work backward to fire the second

Note: blade is not hollow ground

Original U.S. Vietnam War Empty / Inert Composition C-4 Block MG 42 Bolt & Barrel Assembly The original marking looks toOriginal Item: Only One Available. These 1 2 lb C 4 bricks were used by various Army, Navy, and Marine engineers and demolitions units. C 4 is very stable and insensitive to most physical shocks. C 4 cannot be detonated by a gunshot or by dropping it onto a hard surface. It does not explode when set on fire or exposed to microwaves. Detonation can only be initiated by a shockwave, such as when a detonator inserted into it is fired. When detonated, C 4