In this post, I am going to discuss the British Sherman Firefly. And to tell you about that, first I need to tell you some things about some other tanks, the Crusader, the Panzer IV, and the M3 Lee/Grant.
The Crusader was an excellent tank, certainly, but it was unprepared to face off against Germany’s new main battle tank, the Panzer IV. The Panzer IV had better armor, better performance, and an armament that had a drastically superior effective range against the Crusader than the Crusader’s main gun did against the Panzer IV. Even the later models of the Crusader, which mounted a much more powerful cannon, still stood little chance against an aggressive and aware Panzer.
The M3 Lee and Grant tanks were some of the first to mount a cannon which could reliably engage Panzers. There is little practical difference between the “Lee” and “Grant” variations, and mostly consisted of slightly different turret construction.
They were somewhat unusual tanks, featuring a full range 37mm light cannon turret on top of the hull like a normal tank (though this was the time at which engineers were settling on what the future would even call a “normal” tank.) However, mounted on the front of the hull and off to the side was a much larger cannon. Interestingly, while they did not have similar ammunition, this new gun shared a round diameter of 75mm with the main gun of the Panzer IV. The M3 was far better armored than the Crusader, and the hull cannon could engage a Panzer IV reliably at the same distances a Panzer IV could engage the M3.
The Grant/Lee, however, was only in production for a short time, as they were intended to be an intermediary measure leading up to the M4 Sherman. After the introduction of more capable British and American tanks, most M3s were moved to the Pacific front to act as infantry support tanks.
The British used a slightly different nomenclature for the base Sherman variants. The M4 was the Sherman Mk. I. The M4A1 was the Mk II, the A2 was the Mk III, and so on and so forth.
This brings us to the Sherman Firefly. By 1943, the North African front was plagued by Germany’s feared, respected final boss of the battlefield, the Panzer VI Tiger. The Tiger outgunned anything the allies could throw its way, and was heavily armored enough to easily survive most tank-on-tank engagements.
The Tiger was not completely invulnerable, however. The British responded to it with the 76.2mm 17-Pounder cannon. This heavy gun could penetrate even the thick front armor of the Tiger, from over a kilometer away.
The next issue, of course, was mounting the massive thing on a tank. The Cromwell, Britain’s main tank in 1943, simply couldn’t fit it, so they turned to the Sherman.
Even then, few involved in the project were convinced that the Sherman could mount the 17-Pounder, any more than the Cromwell. An engineer by the excellent name of Kilbourn, who worked for Vickers, managed this difficult feat, and spectacularly. He designed a breech and recoil system that would let the massive gun be mounted on a Sherman turret, possibly with the assistance of black magic. Of course, to make the design work, he had to remove a crewmember position entirely, and rearrange most of the secondary equipment such as the radio, to fit even his condensed 17-pounder turret.
Once fielded, the Firefly became just the monster needed to fight the Tiger and Panther tanks. It could engage and destroy both from over a kilometer. Once a Firefly started putting rounds out, German armor had little opportunity to retaliate.
The Firefly had problems, of course. Some of them are very Britishly summarized by Ken Tout of the 1st Northamptonshire Yeomanry:
“The Firefly tank is an ordinary Sherman but, in order to accommodate the immense breech of the 17-pounder and to store its massive shells, the co-driver has been eliminated and his little den has been used as storage space. ... The flash is so brilliant that both gunner and commander need to blink at the moment of firing. Otherwise they will be blinded for so long that they will not see the shot hit the target. The muzzle flash spurts out so much flame that, after a shot or two, the hedge or undergrowth in front of the tank is likely to start burning. When moving, the gun's overlap in front or, if traversed, to the side is so long that driver, gunner and commander have to be constantly alert to avoid wrapping the barrel around some apparently distant tree, defenceless lamp-post or inoffensive house.”
German units quickly made any Firefly tanks their priority targets. An interesting way of disguising a Firefly among other Shermans was devised because of this. The front half of the cannon was painted with a wavy pale pattern on the lower part of the cannon, which masked the distinctive appearance of the 17-pounder cannon to distant observers.
We’ll see the Firefly again in a later post, when I discuss the different types of ammo used by tanks in WWII (and present day).
From here, we will move on to the more irregular applications of the Sherman.