17Pdr CR

[Dandebur]

Hello everybody,
In 2014 I have bought a case of 17Pdr anti-tank ( 76.2x583R).I wonder about the CR. (I had yet one before, same maker, same year, with the classic stamping CF).
Why a reduced charge for an anti-tank gun?
Was it for training with a special shell?
Thanks by advance for your comments.
Regards,
Dandebur.

 

[SHAKY]

The reduced charge was for the HE shell used on tank fitted 17 pdr's etc. such as the Sherman Firefly. A reduced charge was used to allow thinner walled shells to obtain a higher capacity of explosive to be fired safely from a relatively higher velocity gun to increase the effectiveness of the round. Previous HE shells had thicker walls and less explosive so they could be fired safely at higher velocity.