Ordnance QF 17-pounder

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Summary

The Ordnance QF 17-pounder was a British anti-tank gun developed in 1942. The tank is chambered in 76.2x583 mmR cartridges and became the standard heavy anti-tank artillery in the British arsenal from 1943 onward. The 17-pounder earned the reputation as one of the most effective Allied anti-tank weapon in the entire war, mostly due to the prevalence of the APDS shot that can defeat most of the German tanks frontally. It was succeeded as a tank gun by the larger and more powerful 20-pounder gun.

Game Usage

The 17-pounder gives the medium tanks of the British tech tree the ability to fight against the heavier tank armor that will be encountered at the 5.0 - 6.0 battle rating. The cannon presents a large muzzle velocity that gives the shell a very high penetration power. The 17-pounder also has the very powerful Shot SV Mk.1 ammunition, an APDS round that can penetrate around 200 mm at standard ranges. This ammo gives the 17-pounder the power to take on the majority of vehicles at the tier. The downside of the cannon is that there is not explosive filler in any of the armor-piercing shells, meaning that the beyond-armor damage effect is low and will rely on just the passing shell and shrapnel inside the tank.

Guns of comparable performance

Users

17-pounder

77 mm HV

Ammunition

OQF 17-pounder

Ammunition Penetration in mm @ 0° Angle of Attack Type of
warhead
Velocity
in m/s
Projectile
Mass in kg
Fuse delay
in m:
Fuse sensitivity
in mm:
Explosive Mass in
TNT equivalent
in g:
Normalization At 30°
from horizontal:
Ricochet:
10m 100m 500m 1000m 1500m 2000m 0% 50% 100%
Shot Mk.6 160 157 133 112 96 86 AP 883 7.7 N/A N/A N/A -1° 47° 60° 65°
Shell Mk.1 9 9 9 9 9 9 HE 883 7.0 0.4 0.5 883 +0° 79° 80° 81°
Shot Mk.4 165 160 138 108 94 81 APC 883 7.7 N/A N/A N/A -1° 48° 63° 71°
Shot Mk.8 171 168 156 143 130 120 APCBC 883 7.7 N/A N/A N/A +4° 48° 63° 71°
Shot SV Mk.1* 228 226 207 189 159 134 APDS 1203 1.7 N/A N/A N/A +1.5° 75° 78° 80°

* - Only available on the A.43 Black Prince, A30 Challenger, and Centurion Mk.1

77 mm HV

Ammunition Penetration in mm @ 0° Angle of Attack Type of
warhead
Velocity
in m/s
Projectile
Mass in kg
Fuse delay
in m:
Fuse sensitivity
in mm:
Explosive Mass in
TNT equivalent
in g:
Normalization At 30°
from horizontal:
Ricochet:
10m 100m 500m 1000m 1500m 2000m 0% 50% 100%
Shot Mk.6 142 139 118 99 85 76 AP 754 7.7 N/A N/A N/A -1° 47° 60° 65°
Shell Mk.1 9 9 9 9 9 9 HE 754 7.0 0.4 0.5 580 +0° 79° 80° 81°
Shot Mk.4 146 142 122 96 83 72 APC 754 7.7 N/A N/A N/A -1° 48° 63° 71°
Shot Mk.8 152 149 138 127 115 106 APCBC 754 7.7 N/A N/A N/A +4° 48° 63° 71°
Shot SV Mk.1 205 203 186 170 143 120 APDS 1120 1.7 N/A N/A N/A +1.5° 75° 78° 80°

History

Development

Before the 6-pounder saw service in the British Army, War Office were already beginning the development of an even powerful anti-tank gun with the belief that German tank armor would soon make the 6-pounder inferior just like the older 2-pounder. In late 1940, the project for a new anti-tank gun started and its development was complete by late 1941.

Service

Prototypes were being made on a limited basis in Spring of 1942 and were put into unexpected service in North Africa with the appearance of the German Tiger tank. The first 100 17-pounders were brought to Africa and placed on makeshift 25-pounder carriages since its own carriages were not yet developed. These 17-pounders, code named Pheasant, first saw action in February 1943. Fully developed 17-pounders and their carriages were then put into production in 1943 and put to use in the Italian Campaign.

In comparison to every other Allied anti-tank armaments, the 17-pounder was superior in every way. The ammunition is able to destroy most Axis tanks the Allied came across. Its performance in the battlefield prompted its adaption into a tank for a mobile platform. This adaption saw lots of trouble due to the large size of the gun in comparison to the turret rings of the tanks available. The first attempt at a tank mounting was to take the Cromwell tank and modify it into the Challenger tank, but mechanical problems delayed its production. An interim solution was to modify the standard Lend-Leased M4 Shermans from the Americans with the 17-pounders to become the Firefly, which would go on to become the most produced tank that mounted the 17-pounder, though the 17-pounder had to be specially crafted to fit into the Sherman turret. Still, the 17-pounder was mounted onto any tank able to be adapted to mount it, such as the M10 tank destroyer.

The gun was vaunted as the "Allied greatest anti-tank gun", but had flaws. It was rather large and heavy compared to the previous infantry-transportable 6-pounder and was preferred to be carried around by a tractor than on foot, which also emphasize the importance of the gun motor carriages like the Achilles. The much valued APDS round, which can penetrate more than 200 mm in standard combat ranges, had a string of inaccuracy throughout its combat service. Tests at with the 17-pounder show that from 400 yards away, the APDS round hit rate was only 57% in comparison to the APCBC 90%, jumping it to 600 yards already reduce APDS rate to 34%. Though British officers claim that it was due to a "bad round batch" or a defect in the discarding sabot, the inaccuracy problem stayed consistent throughout the war.[1]

After World War II, the 17-pounder still saw action in the Korean War as an anti-tank gun and an infantry support weapon against bunkers. The 17-pounder was replaced in the tank mount by the larger OQF 20-pounder.

77 mm HV

During the war, the British attempted to create a gun small enough to fit on their tanks, firing 75 mm shells at a higher velocity for better anti-tank capabilities. Vickers developed the gun known as HV 75 mm that fired a 75 mm shell from a necked down case from the 3-inch 20 cwt gun to allow a larger propellant charge. This gun was still too large to be used on the Cromwell tank. By the time the Cromwell's successor, the A34 Comet I came about, the gun concept was redesigned to instead use the 17-pounder shells with the 3-inch 20 cwt casings. The gun used a shortened 17-pounder barrel and had a 3-inch gun breech in the design. The ammunition with the 3-inch 20 cwt casing proved to be more compact than the standard 17-pounder ammunition at the drawback of lower muzzle velocity. The gun was able to be mounted onto the Comet turret and became the standard armament of the tank. The gun was renamed as 77 mm HV.

Images

Additional information (links)

References

  1. Moran, Nicholas. "The Chieftain's Hatch: US Guns, German Armour, Pt 1." World of Tanks. N.p., 04 Jan. 2012. Web. 08 July 2016.