German Model 1914 Rod Grenade with Ranging Disc
W.W.I, rod grenade design fluctuated between the simple and complicated,
always a struggle between ease of use, safety, effectiveness and cost of
manufacture. No one design ever achieved the ultimate configuration. Of
course the underlining "Achilles Heel" was no matter what, they still trashed
the rifles used to fire them.
One of the more technically advanced designs (In my humble opinion) is this grenade. It rivaled many artillery rounds in its fuze design and certainly didn't lend itself to economical mass production. Still, on its own merits, this grenade exhibits a combination of features that field experience proved useful:
The unique “Ranging Disc” is used in one of three modes. Removed for maximum range, curved face forward for ½ range or as shown for ¼ range. The rifle was always placed at one angle for firing (typically 45 degrees), a useful feature in the confined space of the trenches.
The fuze utilizes an interesting safety feature. It consists of a releasing socket holding a locking ball in place which retains a striker with a folded firing pin (needle). Upon firing the socket is pushed down, overcoming a pair of bent flat retaining springs, releasing the ball which allows the nose/striker assembly to spring up (big spring), freeing the striker to push down (small spring) against the needle unfolding and locking it. It is now armed and functions as a simple impact fuze.
Sectional View Copyright© 2002
While all very clever, rod grenades were still very hard on the rifles that fired them and were complex to make (incorporating the features desirable). By 1917 the rod concept was abandoned in favor of the cup launcher.
During WWII, however, this was re-visited in a small way by specialized grenades made for flare pistols (Wurfkörper) and even a very large anti-tank grenade (3.7cm Aufsteck Geschoss) developed for the 37mm Anti-Tank Gun.
(Return to the Rod Grenade Overview Page for more info on that currious footnote in history.)