Allied guns and Panthers, oh my!

[Vark]

With the arrival of the Allied forces in CMBN, I thought this article, from the Chieftains Hatch, might be of interest.

http://worldoftanks.com/news/919-chieftains-hatch-us-guns-vs-german-armour-part-1/

[gunnulf]

Cheers for that, very interesting, particularly the level of poor intel on panthers before D-Day. I knew the yanks had turned down offers of Hobarts funnies which obviously complicated matters on Omaha to the near point of failure but I didnt know they had turned down 17pdrs and made a conscious decision of leave 76mm gunned M4s behind for logistical/complacency reasons.

[Erwin]

Interesting site. Thanks.

[JonS]

I knew the yanks had turned down offers of Hobarts funnies which obviously complicated matters on Omaha to the near point of failure

That isn't really true.

http://www.amazon.com/Cracking-Hitlers-Atlantic-Wall-Engineers/dp/0811705897/ref=sr_1_3?s=books&ie=UTF8&qid=1326231912&sr=1-3

In particular, Appendix B, p.242-244 (most of it can be read on line at Amazon)

[Rayak47]

I recently read in "Deathtraps" by Belton Cooper that Patton successfully lobbied to put the Pershing program on backburner and dedicate production to Shermans because he thought tanks should bypass tanks and not go head to head?

[Sgt Schultz]

Good read.

More reasons to buy Panthers in QBs.

[c3k]

76mm had SERIOUS issues with muzzle blast. That was part of the armored commanders' concerns. They went so far as to consider how to implement paired shooting, where an offset tank offers corrections to the tank which just fired. That was needed because the tank that just fired couldn't see beyond the cloud of smoke and dust to "sense" the shot.

[JonS]

I recently read in "Deathtraps" by Belton Cooper that Patton successfully lobbied to put the Pershing program on backburner and dedicate production to Shermans because he thought tanks should bypass tanks and not go head to head?

IMO, Cooper is great when he talks about stuff he did, places he went, and things he experienced. All the more so because there just aren't that many memoirs from non-teeth arms junior officers.

Cooper is much less than great when he starts babbling on about things which he has no direct experience.

Patton's thoughts, or lack there of, on armoured warfare very definitely fit into the second category.

[akd]

76mm had SERIOUS issues with muzzle blast. That was part of the armored commanders' concerns. They went so far as to consider how to implement paired shooting, where an offset tank offers corrections to the tank which just fired. That was needed because the tank that just fired couldn't see beyond the cloud of smoke and dust to "sense" the shot.

I've always wondered about this one. Did it have serious muzzle blast issues, or serious in comparison to the standard short 75mm? Did it really have more of a problem than, say, the German 75mm L/70?

[hoolaman]

Interesting too the notes about the poor accuracy of APDS in that time.

20% hit ratio at 800 yards on a static target? The test firing indicated that they couldn't get enough accurate hits on a static Panther to make a conclusion.

[Michael Emrys]

About 30 years ago I saw a film that was alleged to be of a 17 pdr shot in flight. Briefly, each frame of the movie was said to be taken by a single-exposure camera tripped by an electric eye as the shot went past. Then, each frame was developed and then edited into a continuous movie that lasted five or maybe ten seconds. The reason I bring this up is that I was really struck by how much the shot wobbled in flight. It wasn't hard to see how that would adversely effect accuracy.

Michael

[hoolaman]

IIRC it was something about the discarding sabot not discarding right. A rod with half a sabot stuck on it is less than aerodynamic.

[Steiner14]

I've always wondered about this one. Did it have serious muzzle blast issues, or serious in comparison to the standard short 75mm? Did it really have more of a problem than, say, the German 75mm L/70?

Ofcourse they had. The german muzzle-blasts were BY FAR the lowest. One shot with a german gun and you saw almost nothing. One shot from a russian or US gun, and you saw a big cloud... Why do you guess, were the wonderful Alliies so keen on "liberating" the Germans even from the rest of the not destroyed and still functioning german industry, robbed all papers, patents and were even keen on the 3rd generation of engineers?

[akd]

Hmm..not the same thing really, although I guess frequently used interchangeably. The ammunition issue would be muzzle flash and smoke obscuration, rather than muzzle blast (overpressure created by the escaping gases which can kick up dust and debris). Makes more sense if smoke obscuration was the issue, but again, I doubt there was anything special about the 76mm other than it using than lot more propellant than the short 75mm. If Allied ammunition was the issue, we would expect similar problems with the 17 pdr., 90mm, etc., although barrel length in combination with the ammunition can play a role.

[Vark]

Ofcourse they had. The german muzzle-blasts were BY FAR the lowest. One shot with a german gun and you saw almost nothing.

(3 min plus mark).

Why yes Steiner, if it was not for the bubble wrap pop I'd hardly know those tanks were firing! Why must you extoll the German equipment to such ludicrous degrees, it just diminishes any argument you have. It's obvious from the footage that German tanks produced less of a firing signature but obscuration was evident and varied, depending on weather conditions. There is other footage, taken from within a Tiger showing a full 1-2 seconds of obscuration after firing, so the gunner would have to rely on the commanders low powered binoculars for the fall of shot.

[Chris69]

Not to mention the lack of any sources or the absolutely unnecessary political agenda included in Steiner's post.

Schneider even mentions the necessity to have other tanks observe round impacts in "Panzer Tactics" (Defense chapter), because smoke from the discharge could obscure the target for several seconds.

[MikeyD]

I recall into the 1960s reports of US M48 tank 90mm APDS having similar problems. It wasn't so much that that round was 'inaccurate' than that it was 'erratic'. When it hit the target it hit the target - when it missed it didn't just miss by a meter oer two, it shot off at a crazy angle. Apparently had to do with whether it separated cleanly from the sabot or not.

[LemoN]

Hmm..not the same thing really, although I guess frequently used interchangeably. The ammunition issue would be muzzle flash and smoke obscuration, rather than muzzle blast (overpressure created by the escaping gases which can kick up dust and debris). Makes more sense if smoke obscuration was the issue, but again, I doubt there was anything special about the 76mm other than it using than lot more propellant than the short 75mm. If Allied ammunition was the issue, we would expect similar problems with the 17 pdr., 90mm, etc., although barrel length in combination with the ammunition can play a role.

Below are just two of my uneducated guesses.

I'm not entirely sure if the Germans also used smokeless powder within their AT guns, but if small arms are anything to go by then that would mean that allied guns would produce much more smoke than German ones, given the fact that they'd only use semi-smokeless powder. Also, I would suppose that the lack of a muzzle brake would kick up more dust directly in front of the tank instead of to the sides, resulting in more dust directly in the FOV under certain conditions.

But yes I agree, saying that you wouldn't see much if any obscuration after firing is, of course, complete bollocks.

[GLynn41]

I too have wondered about the76mm blast-- Steven Zaloga says the 75 mm had 1.5# of propellent--- the 76mm 3.2 and operated at about 38,000 psi- the L70 had 8.2#-and operated at 48,000+ or-

In the process of puting a 76mm in the M4-- they cut 15" off the barrell- some of the compliants about the round were smoke, obscuration, it could be the round and propellent were optimised for the longer barrrel -so the smoke and blast went way up in the shortened barrel-- a long primer that ran from the base of the hull to the base of the shell was used later and helped with the smoke-- it would seem that the cutting of the barrel not only lowered the velocity but may have cause d other problems as well-- one last thing -- the 76mm was at times a Naval weapon -- so smoke and balst were less of a concern

[Michael Emrys]

...one last thing -- the 76mm was at times a Naval weapon -- so smoke and balst were less of a concern

There was indeed a 3" naval gun, but my understanding of the 76 mm tank gun is that it was derived from the 3" AA gun, a different lineage. Do you have information that could sort this out?

Michael

[GLynn41]

I will look I may have wrong

[GLynn41]

on page 106 in Armoured thunderbolt -by Zaloga-"Ths best american antitank gun of the time was the 3 inch gun, which had been derived from WW1 antiaircraft and coastal defense guns" he goes on to write that it was reworked to be M1A1 76(T1) -as the 3" in the M10 was too large to fit the Sherman turret- the 76 mm was cut down from an L57 to L52.

M. Green does not mention the history

Hunnicutt does not mention the history of the weapon just its adapation

If one will go to Scribd ---Zaloga and hunnicutt are there to be read and much more

[JonS]

I know the US 3-in and 76mm are both the same calibre, but for some reason I think they're different guns with different lineages. Anyone?

[Steiner14]

(3 min plus mark).

Why yes Steiner, if it was not for the bubble wrap pop I'd hardly know those tanks were firing!

Ahem, you are talking about a 88mm gun, don't you.

The video you present gives not a good impression. Ofcourse if the ground is dry and dusty, then you will see lots of "smoke" and it could even blind the commander for several seconds (German dug in ATG crews had to make sure, there was no dust from the ground being produced).

I have searched a video for you, where you get a better impression, of the smoke of the 88 gun, if you want to compare apples and oranges (signature of the 75mm was less). In this video (@2:55) you can not only see how fast the smoke disappears (at typical engagement distances of 1000m the smoke of even a 88 was gone, before the shot was heard), but also the low density of the smoke:

http://youtu.be/PLAI1omJnAo

I don't understand why you have problems with simple facts. This fact even shows how tough it was for allied tankers to fight german tanks and it is a proove of bravery of the enemy tank crews.

@Chris69

If you know nothing about this topic (which is no surprise to me) i can recommend the book "Unternehmen Patentraub 1945" by Friedrich Georg. But i don't know if it's available in English.

As a quick introduction for English readers to this interesting but taboo topic, i can recommend this article:

http://www.wintersonnenwende.com/scriptorium/english/archives/articles/patents.html

[Wicky]

Not taboo as this book is in bookshops and available online, and yup German civilian & military tech was unashamedly purloined wholesale by the allies as way of compensation for all the hassle that the Allies had to put up with for 6 years....

http://www.amazon.co.uk/T-Force-Race-Nazi-Secrets-1945/dp/184529727X

Recommended reading, without the Kettlerian drivel found in Steiner14's link.