Sources show that the M12 Self Propelled Gun was fielded by six battalions from 1942 through 1945 before being disbanded after the war: 174th, 258th*, 557th, 558th, 987th and 991st Field Artillery Battalions. All six battalions served in the European Theater of Operations. Even though the 558th guns were well worn from action in Europe, the battalion embarked in August 1945 on the USS Breckenridge to the Pacific Theater of Operation in preparation for the invasion of the Japanese home islands. Luckily, Japan surrendered as their ship was heading to the Panama Canal. To the relief of the war weary veterans, the Breckenridge was diverted home to New York City.

*Greg Matthews' research note from 12/28/09: It appears that my search for 258th photos and the M12s will not be successful. Reason, after additional research and information provide by the Col. the historical officer of the 258th, it appears that the 258th was not equipped with the M12s. When the original 258th was federalized its two battalions were split. 1st Battalion remained the 258th and the 2ond battalion became the 991st FA. In 1943 when the M12s were accepted by War department, the 991st got the "new gum", the M12 155mm gpf. The 258th kept the 155mm gpf "Long Toms" towed artillery. Whether the 258th was later equiopped with the M12 is not known or clear at this point.

*Craig Schneider note on 4/19/10: I found your website recently while searching for videos of the M-12. Just noticed the note posted in December about a fellow searching unsuccessfully for photos of the M-12s in the 258th and being unable to confirm if the unit ever had them. As far as I know, the 258th did use the M-12 in Europe. My grandfather served in Headquarters Battery of the 258th and took quite a few photos of M-12s in France and Germany, including a few of him in or on M-12s, which I must assume were the 258th’s and not those of another unit.

Gun Nicknames

Most M12 guns received nicknames from their crews. These nicknames were painted on the sides of the vehicle. Aiming Circle Annie from Battery A used a crewmember's girlfriend's name Annie along with Aiming Circle that was a device used to aim the gun at a target. Ali Babba, also from Battery A, and Bouncing Betty from Battery B were names with no remembered background.

Aiming Circle Annie achieved national fame when Newsweek magazine featured a photo on the front cover of that gun crew firing their M12. This photo has also been seen in many other publications and books. The men in the picture are: Dick Smuin firing the gun, Sgt. Marcelo and Bill De Pauw standing, and Baten kneeling. In another photo showing the loading of the gun we see (left to right): unknown, Walker, Ruiz, De Pauw (the gunner), Wells, and Marcelo.

Gun Background

The M12 guns were a combination of a tank chassis with a shortened artillery gun mounted on it. The 588 th had 155mm guns that were originally coastal defense guns along the California coast. Other M12 battalions might have had newly manufactured barrels but the 558 th M12s were built from older artillery pieces. The barrels of the M12 were about 18 feet long. There was another vehicle designed after WW2 using a longer 155mm barrel that was called a Long Tom.

The 155mm guns could shoot several types of shells (or projectiles). A high explosive could be used for other ground targets or used with a timed fuse to achieve and aerial explosion for anti-personnel action. They also had a white phosphorous shell for starting fires or for particularly devastating anti-personnel fire into a pillbox or gun emplacement. For destruction of concrete pillboxes, one or two armor piercing shells were sufficient. The gunner would sight down the bore of the gun from about 250 yards away. The veterans said they could put two armor-piercing shells into the same hole at that distance. One shell would usually disable the gun crew just from the concussion. Two shells were often fatal to all soldiers in the pillbox.