The Big Bang Model 155MM was introduced in 1958 along with the 60MM and 105MM cannons.
The 155 uses the same barrel/breech as the 15FC, but with the addition of some modernizing
features like recoil tubes and rubber tires to help the toys appeal to the children who
were seeing WWII newsreels.
Like the 15FC, the barrel titlts, but not very much at all.
The 155MM has always been produced with an olive drab (OD) finish. As with the 60MM
the 155MM is found with both the Primere tires and the current tractor tires.