M4 Sherman gun

.350 Remington Magnum - 1965.

The powder wouldn't present a problem. You could even plug the case and put an inert substance in the forward half or third. We used to do that with black powder cartridges for "plinking" rounds - just drop in a .45 caliber wad over the powder and fill the rest with corn meal.

 

By some people's standards, the German gun sight was overly complicated. The gunner had a ring that he turned so he could call up three different reticules: AP, HE, and co-ax mg. It was a typically German engineering solution but it worked. I don't see why we couldn't have something similar. I guess the military bureaucrats were locked into their standardization for the maximum production mindset.

 

The Zeiss sight used on panzers did just that. They had two range arcs, the inner one always being for AP rounds and the outer one for HE.

For more info on the subject...

http://www.75thguards.com/ww2online/downloads/Zheriz_Ziess_Sight_Guide.pdf

 

I'm not disputing that fact. Simply saying that like many things on both sides they simply chose wrong, or didn't realize there was a choice
to be made until after production lines had been set up, and then decided that fixing it wasn't worth a disruption of production when the
75mm sherman still made up 1/2 of the US tanks in service and the war in Europe looked to be over in 6 months.

 

I think you've probably nailed it. The complaints about the performance of the 76mm HE round wouldn't have really filtered back until late fall of 44 or so. It probably looked OK to some guy in the states shooting at a cinder block wall, with nobody shooting back.

 

Sorry I have not responded of late, a deadline due. But I have enjoyed this thread as I have wondered for years which this issue even existed and I think it is one of those combination of things. Lots of little reasons. I do think the velocity could have been lowered easily in 1944 as KB said. It may seem a small thing to discuss but to a tanker the thought of stronger armor and a better gun along with better food was probably on their minds.

Some months ago I read Harry Weide's "Tank Killers" exploration of US Tank Destroyer concepts that gave great insights into how Ordnance decisions were made, something lots would enjoy..............if that is the right word!....And it is on Kindle !!

 

In regards to the HE round on Shermans it's also worth noteing that late in the war (and in Korea as well) Shermans were used as indirect fire artillery on a number of occasions, indeed I've seen at least one photo (in Korea I think) of a Sherman surrounded by a massive number of ejected cases. The performance of the HE round could be of considerable import in cases like this. How much that was taken into consideration at the time is another matter.

 

I suspect HE was of secondary importance to German tanks because their default targets were armoured fighting vehicles. The UK build as many as Germany and the USSR and USA each added more than twice the UK's number.

For the Allies it was the other way round: German tanks were nowhere near as numerous as soft targets. Particularly in the UK's long time no.1 theater, the western desert, where HE performance was needed to deal with the pesky dug in AT guns. The 75mm gun finally provided that and could at the same time kill any Germany tank in 1942 and almost all in 1943.

And last but not least, the 76mm had the weaker shell but the better accuracy usually more than compensated for this. Hence the frequent use of M10 as 'assault guns' firing HE.

 

Just as with aircraft, cars, tanks and small arms some designs are simply better than others,

The 75mm gun in the M4 was a version of the French 75mm 1897 - designed as a field gun to hurl HE and shrapnel. It was was a classic design, which is why . it was picked at the main armament for the M4, the first western tank to have a turret mounted main armament capable of AP and HE. .

The US 76mm gun was designed as an anti tank gun, and had a less effective HE Round than the 75mm. The 76mm HE shell was designed with a thicker casing than the 75mm to withstand the higher firing stresses. This may have been a clumsy design as the Germans seem to have managed to retain an effective HE for the long 75mm.

 

Replacement was gradual. First Army gave some M4(76) tanks to the 2d and 3d Armored Divisions and those tanks saw a lot of combat, especially during Cobra. More M4 tanks with 76mm guns were shipped to armored divisions to replace losses as they became available. In the Third Army, however, M4(76) tanks were rarer. Patton reportedly did not want his troops to worry about new weapons and equipment to which they were not accustomed, and only issued M4(76)s to separate tank battalions on an experimental basis. However, by around August or September of 1944, armored division commanders began to pressure tankers to take the 76mm gun armed tanks as their new mounts, presumably due to lessons learned. Even so, rank-and-file resistance towards the newfangled 76mm persisted in Patton's Army. For example, Col Creighton Abrams, commander of the 37th tank battalion, 4th Armored Division, had to switch his personal tank to a M4(76) to set an example in order to encourage confidence in the new tank. During the same unit's embroilment in a massed armor battle in Arras, Lorraine, only company command tanks had the 76mm gun, and tactical leaders often had to personally engage targets. In spite of winning a decisive victory, the experience of intense tank versus tank combat finally prevailed on the enlisted men that the 75mm gun was inadequate against the Panzers, and 76mm guns, along with applique armor, became universal in all US Armies. The ratio of 76 to 75 gun armed tanks steadily increased in the last two months of 1944, but dropped precipitously during the Battle of the Bulge, presumably due to heavy combat losses.

The dire need for a tank gun more powerful than the 75 began painfully evident during the Battle of the Bulge. In pursuance to numerous complaints from tankers and armored commanders, Eisenhower informed the War Department to send no more M4(75) tanks to ETO in early 1945, amidst a severe shortage of medium tanks that reached the proportions of a crisis. After this time only M4(76) and M4(105) were sent as replacement tanks to Northwestern Europe. By the last month of the war there were slightly more 76mm gun armed M4s than the 75mm variant in the First Army.

 

I believe there was some doubt about how effective an HE round could be from a flat trajectory round (high or medium velocity). Infantry targets entrenched or even in the open were difficult to hit with flat trajectory rounds. I recall one tanker describing bouncing rounds short of the target to get an air burst just over the target. Whether that is really possible I don't know but some believed it.

The most effective HE was delivered by high angle fire which is probably why the US had assault guns like the M-8 and M-4(105).

 

IIRC, the Germans used the same practice, at least for the Panther and Tiger, of bouncing or skipping their HE rounds to air burst above the intended target - an AT gun or entrenched infantry, since a direct hit on the target would not necessarily trigger the fuse.

 

This good thread continues to generate interest.

Sheldrake: I think " clumsy design" sums it up nicely. A very good anti-tank gun that fit the turret ring nicely. That they could only think of thickening the projectile wall to withstand the increased pressure instead of loading propellant to a lower pressure is odd. There probably is another explanation but may never been known. It appears to be a clumsy attempt !

Triple C: Nice write up: I have heard od not wanting to change the tank (M4) even from Patton, but never heard the crews did not want the 76 gun. It makes a certain sense, they were use to it probably comfortable and relied on reflexes in combat but seeing a Panther or one of the Tigers in the Ardennes would seem to over ride that. Was it that different to use, slow to learn? I would have to think I wanted the better anti-tank gun but who knows. I am currently reading Hugh Cole's "Ardennes" and he credits two generals with says they wish the US had 90's on their tank. But it seems by then most may have wanted the new gun.

Earthican and Takao: You two have me curious again. I thought, perhaps erroneously, that air burst were achieved by time in flight fuses, or in anti-aircraft proximity fuses as well, If shooting an HE projectile and ricocheting it off relatively firm ground what would cause it to explode in the air at approximately where you wanted it....or just anywhere for that matter. Did tanks carry timed fuses ? If so why bounce. It they shot HE it seems it might go off on ground contact or if it did not then what would set it off on it's second flight. I do not know enough about HE projectiles to say it is not possible but it seems implausible.

.I happened to watch "A Bridge too Far" the other day and noticed the Shermans playing Fireflies, the several actual tanks that I think were bought or leased from Argentina or somewhere in SA, had barrel sleeves that looked similar to a Tiger. The 76 and 17 pounder did not so I gather they were rearmed at some point post WW2. Anyone know with what ? The follow up tanks were mockups.

Gaines

 

Have also read where the aim would be to bounce under the tank. On roads, flat ground...How many actions would one have to be involved in, in order to discover "bouncing"? - thinking many. Or command tank observed shell behaviors and reported. Either way, very interesting.
Also, good to see CCC back in form.

 

It wasn't a timed fuse as much as a time delay fuse.

From wiki

The bounce would start the fuse allowing a mid air detonation.

Reminds me of that P-47 documentary. https://www.youtube.com/watch?v=Sj3Usgfhdls
no idea how well bouncing 50 cals actually worked. Probably shook up the crew if nothing else.

 

Roadwheels, idlers and so on were not made from armour grade steel.

 

I have always the "bounce your 50 cal shells to hit the underneath" to be utter crap. Hitting the damn tank at 300mph from distance is hard enough. How do you judge the angle? What angle is needed so it comes up to hit the underneath? How far away from the tank do you need to hit the ground to bounce it underneath? Is the angle different on different surfaces? etc etc plus many other variables that mean this is rubbish, not to mention the reduction on the effective penetration of a round slowed down by hitting the ground and then striking underneath at a less than ideal angle.

 

I think 'utter crap' sounds reasonable. You need the right surface to have .50 bullets bounce off and they'd go into tarmack, so you'd need a roadsurface of cobblestones. They did have that inside towns but AFAIK outside it was dirt or tarmack.

 

I think on any surface it would be impossible, the angle you would need to approach to get them to bounce off would mean being impossibly low and even then does anyone not think it suspicious that if they'll bounce of cobbles that they won't at a similar angle bounce off a steel plate possibly an inch think and practically thicker due to the angle of impact.

 

Pacifist: Many thanks. That at least sounds more plausible and I can see it working.. I had not thought of a time delay fuse of the type fitted to naval projectiles. I had not thought of a glancing blow setting off the delay fuse. It makes since to penetrate a tank's armor then explode. Some of the later stuff turns the tank's own armor into shrapnel such as the time delay HESH does . But HESH would not bounce well!!! It is amazing how creative people get when it comes to killing each other !

Weapons are fascinating except for the carnage they cause. I appreciate your input.

Gaines