Large quantities of German concrete stick, or "potato masher", grenades
have been recovered in various areas of the European Theater. Although it
formerly had been supposed that such grenades were local improvisations,
evidence now suggests that their design has been accorded official recognition.
Two types have been found.
Type 1 consists of a wooden handle, rectangular in cross-section, with a 3/8-inch-square
groove running the length of the handle. A length of cord, attached to a pull fuze,
operates through this groove. Often the other end of the cord is tied to a
small piece of wood, which serves as a pull knob. This is wired to the end of
the handle with soft, easily broken shear wire.
The forward end of the wooden handle is slotted to form two prongs similar to those
of a tuning fork. Iron wire is wrapped around these prongs, partly to strengthen
the concrete, but chiefly to secure the concrete head to the handle. The head
has a hollow core to accommodate a standard stick TNT demolition charge 1 1/4 inches
in diameter. Two metal inserts above the wooden prongs reinforce the cavity,
and permit the insertion of the standard stick charge.
At the base of the concrete head is a small square of translucent waterproof
paper over a cardboard square of equal size. There is a hole 3/4-inch in
diameter in the center of the card-board, to admit the igniter to the bursting
charge. This hole is aligned with the square groove in the handle.
|German concrete stick hand grenade, Type 1, with
stick TNT inserted in the cavity.|
|German concrete stick hand grenade, Type 2, with stick TNT
embedded in the concrete.|
Type 2 resembles Type 1, but is much simpler. Instead of a hollow in the head of the
wooden handle to hold the stick charge, a semicircular cavity is milled into
the wood, the explosive charge is placed in this cavity, and the whole assembly
then is centered in the concrete mold. It will be noted that in the case of
Type 2 the charge is actually molded into the concrete, and projects about
3/8 inch on the end toward the handle.
In both types the explosive charge is the stick TNT demolition charge,
Bohrpatrone 28, containing about 3 1/2 ounces of explosive and coated with
waxed paper. The stick is 4 inches long, slightly more than an inch in
diameter, and has a threaded aluminum insert cast into the explosive to
accommodate standard German detonators. The usual detonator well is cast into
the stick, and the cavity is sealed with a red sticker, which denotes the
presence of TNT. The standard B.Z. 24 friction pull fuze, having a delay
element of 4 to 5 seconds, is used.