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From: wbt@cbema.att.com (William B Thacker)
Newsgroups: sci.military
Subject: Re: What's an "I" tank?
Message-ID: <1991Apr24.054739.19182@amd.com>
Date: 23 Apr 91 05:20:59 GMT
References: <1991Apr16.041123.27184@amd.com> <1991Apr17.055732.14098@amd.com> <1991Apr18.033039.22899@amd.com>
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From: wbt@cbema.att.com (William B Thacker)


bxr307@csc1.anu.edu.au writes:
>	Also something which both you and Bill have missed is that the
>penultimate infantry tank, the Churchill, was equipped with a 75mm gun (in
>fact the early versions were 6pdrs resleeved to take a 75mm tube) which had
>been designed from the start to fire HE rounds.  

I didn't exactly miss it.  The first marks of the Churchill were armed with
2-pdr turret guns and a 3" howitzer in the bow plate (a Close Support
version reversed the gun positions).  The Mark III switched a 6-pdr for the
2-pdr.  Not until the Mark VII (1944) was the 75mm version produced, though
troops in the field had refitted a number of Mk IV's in January '43, and 
more Mk IV's were upgraded with the 75mm as Mk VI's in December '43.  The
6-pdr to 75mm conversion, BTW, was inspired by the success of the US-built
75mm gun tanks (Grant/Lee and Sherman) in North Africa, and the gun was
specifically designed to fire American ammunition.

>	Finally, I think in criticising the infantry tanks as being unable to
>fire a HE round which would be used against infantry rather misses the point of
>why these vehicles were developed.  They were designed to support the infantry
>in their attack _and_ protect them against other armoured vehicles.

I think the issue being questioned is the wisdom of that theory.  Germany,
the USSR, and even France recognized the need for dual-purpose guns in
tanks.  French tank guns as small as 37mm were equipped with HE rounds.
The Soviets opted to equip the T34 with a 76mm gun despite the superior
armor penetration of the 57mm competitor, specifically because of the 76's
better HE capability.  And while, as Brian points out, the German Pzkw III,
their intended main battle tank, was originally fitted with a 37mm gun, 
it's worth noting that it's design specifically allowed room for upgrading
to a 50mm weapon (with HE capability).  This upgrade was performed
beginning in 1940/41.

(For the US Army, I make no apologies.  We were as clueless as anyone at
this time.)

Britain used the 2-pdr in every gun-armed tank ready for combat in 1939,
save for a small minority of CS vehicles.  They essentially put all their
eggs in one basket, and in so doing seriously compromised their tank
program for several years.  Not until 1944 did British tank guns 
begin to catch up with the standard of the day.  I think there's a valuable
lesson here; a diversity of equipment is important, and
over-standardization should be avoided if possible.

I'm not trying to run down the British armament ministry with the weight of
history; but failures should never be ignored, including this one.

-- 
Bill Thacker	AT&T Network Systems - Columbus		wbt@cbnews.att.com