[A 1] Originally a naval gun, it was also adapted for land service when it became clear that some of the ships for which it was intended would be delayed and that it would be very useful on the Western Front.

They were originally designed as the main armament of the Bayern-class battleships, but were deployed in fixed (Anschiessgerüst) and semi-portable (Bettungsgerüst) concrete emplacements that took weeks to months to build.

[1] One obvious change made for land service was the placement of a large folding counterweight just forward of the trunnions to counteract the preponderance of weight towards the breech.

[2] To meet the demands for more mobility and a faster emplacement time, Krupp designed a combination railroad and firing platform mounting (Eisenbahn und Bettungsgerüst - E. u.

Some guns were also emplaced in the Pommern (Koekelare) and Deutschland coastal defense batteries on the Flanders coast protecting occupied Ostend.

From May 1918 they used a removable steel box (Bettung mit Eisenunterbau) in lieu of the concrete that shortened the construction time, although the exact amount is unknown.

Three "Max" guns participated in the 1918 German spring offensives and two bombarded the French during the Second Battle of the Marne.

[9] One gun was found abandoned in a railway station west of Brussels in November 1918 by the Belgian Army, but the seven others had been evacuated to Germany before the Armistice where they were to be emplaced on coast-defense duties.

There was also a second, smaller, gun (a 28 cm SK L/40 "Bruno") captured which now is mounted on display outside the Australian War Memorial in Canberra, Australia.