British Q.F. 4.5 inch howitzer Mk II

British Q.F. 4.5 inch howitzer Mk II. A breech-loading artillery piece fitted with a sliding breech block, axial recoil system, splinter-proof shield, and steel box carriage. The gun is fitted with two wooden spoked 'Wheels 2nd Class 'C' No 45', and is equipped with drag ropes, spare shovels, rammer, and leather sight and tool boxes.

Impressed on the breech block is '7-3-9 / Q.F.4.5. INCH HOWR MARK II / C.O.W. [broad arrow mark] 1918 / No 3233'. An impression on the side of the breech assembly reads 'Q.F. 4.5" HOWR / C.O.W. [broad arrow mark] 1916. The breech mechanism handle is impressed 'QF. 4.5 C.O.W. / [ILLEGIBLE][broad arrow mark] 1918 [surmounted by 'II'] No 2695'. On top of the breech assembly is the safety stop trigger lock surmounted by the word 'SAFE' impressed into the breech jacket. The howitzer is painted in a modern three colour camouflage scheme, the pattern and colour of which is based on photographs and artworks of similar weapons in the Memorial's collection

The weapon is fitted with a No 7 dial sight dial sight positioned behind an aperture in the top left hand side of the shield. A reproduction brass plate (cast from an original plate) on the hydraulic buffer reads '4.5 INCH Q.F. HOWITZER. MARK I.L. / INSTRUCTIONS FOR FILLING BUFFER / RELEASE FRONT COVER OF CRADLE. DRAW PISTON ROD OUT AS FAR AS POSSIBLE. DEPRESS GUN MUZZLE. FILL THROUGH UPPER HOLE IN REAR OF BUFFER 9 PINTS OF BUFFER OIL. / PUSH HOME PISTON ROD SLOWLY KEEPING THE LINE ON THE END OF THE PSITON ROD NUT, VERTICAL. / SEE THAT BUFFER IS FULL. REPLACE PLUG AND COVER.' The brake system and the dial sight carrier are also modern reproductions.

The QF [Quick Fire] 4.5 inch howitzer was initially brought into service in 1909. The Mark II was introduced in 1917, rectifying a breechblock design defect in the earlier Mark I. The gun was capable of firing a 16 kilogram shell to a range of almost 7 kilometres, however it was its capacity to fire at elevations of up to 45 degrees that made the weapon so effective. The high elevation allowed the gun to lob shells almost vertically into areas protected by traditional fortifications. The heavier 4.5 inch high explosive shell was found to be far more effective than the 18 pounder in damaging enemy parapets and trenches and thus found increasing use for this purpose.

Over 3,300 4.5 inch howitzers were manufactured during the First World War. The Mark II design remained in service into the Second World War when they were finally replaced by the QF 25-Pounder.

The 4.5 inch howitzer did not see operational service with Australian units until after the AIF transferred to France. Following the necessary re-organisation required to bring Australian artillery units into line with British formations, separate howitzer units were formed in February 1916, when the AIF was in Egypt. One howitzer battery was added to each brigade, giving four batteries to each of the five divisions, although the 15th Field Artillery Brigade (5th Division) did not gain a battery. Originally each battery was equipped with four 4.5 inch howitzers – this was increased to six guns in January 1917.

The service history of this particular weapon is not known. However, during the late 1930s, as with most weapons of this type, the weapon had its axle re-worked to allow it to be pnematicised. This process also saw the brake assembly removed. The Memorial re-instated the correct axle configuration during restoration work in 2014. This work aslo saw replacement of missing elements with newly fabricated components, such as the brake assembly and the dial sight carrier. The camouflage scheme applied in 2014 by the Memorial represents a late war multi-chrome scheme seen on many Allied field guns from 1917 onwards.