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Some questions about the US 140mm gun thread


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post-1581-0-21471900-1459744282_thumb.jpg M1 CATTB

pic from TankNet.

I feel uncertain whether its cannon's caliber was 140mm or not, I found a figure at the document AD-A228 389 showed behind, which label the gun as LW 120.But in many ways I've found its data in websites all considered to be 140mm.


AFAIK,the first xm291(140)demonstrator was based on xm1 tank, and the successor was the''Thumper'' which was fitted with a new turret look like the CATTB but still m1a1 hull(Maybe it was CATTB's predecessor? )

post-1581-0-73322100-1459746725_thumb.png post-1581-0-18190300-1459754915_thumb.jpg

I will really appreciate if anyone have valuable information to share

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well,i didn't get much information about it,but seems like Thumper and CATT-B with 140mm gun were both exist



this picture showing Thumper with the ATAC or i believe it is


compare to the CATT-B with 'XM291',the bore evacuator are different, but just compare each other,the size of the gun are very close to each other , and the barrel part out of the thermal sleeve looks the same

i guess they are both XM291 but in early or late version 

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Yes, the ATAC also had an 120mm demonstrator based on M8 Thunderbolt ,compared to the cannon on CATTB it was a bit short...

What I concern about is which one was actually mounted on the tank in photo.


The gun on the 1st picture you posted looks to be the 120mm version, I could be wrong on this so don't quote me, but the bore evacuator on the 140mm appeared much smaller in proportion to the gun on the 120mm version if you compare them side by side, the photos Akula posted seem to show this aswell.

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Well,I dont mind, after all, I'm just a freshman here. Obey the tradition is what I should do.

However,I found I cant post any picture from my mobile phone successfully. It seems that there are some limitations on the file size.


i do everything by URL, i recommend using imgur as a way to store host photos. 


No problem and welcome to SH  :)

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Here's some figures about 140 mm tank gun ballistics that I don't understand. 


Article Here


Since its from Switzerland, I assume this relates closer to the Pz87 140 mm prototype instead of any US project but is still probably relevant.


900+ mm of penetration with KE penetrators vs 750 mm of pen with 120 mm KE penetrators seems like a decent upgrade in firepower. 

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The preference is for non-anime/manga avatars, but there's no strict policy against it.

There's a certain critical mass a forum can reach where everyone has cartoon avatars and I'd like to avoid that. You can imagine a certain kind of person with a serious technical background getting on a forum and seeing Japanese anime girls everywhere and that driving them away, I'm sure.

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I'd be curious to see how the American 140mm compared to the one the Swedes were considering for the Strv 2000 concept.


Incidentally, tank-net says a whole bunch of concepts were considered for the Strv 2000;



Conventional turret with autoloader
Crew - 3 men
Combat weight - ~60 metric tons
Engine - MTU 883
Armament - 140mm gun with 40 rounds and 2x7,62 MG's


Conventional turret with autoloader
Crew - 3 men
Combat weight - ~60 metric tons
Engine - MTU 883
Armament - 140mm gun with 29 rounds, 40mm AC with 148 rounds and 2x7,62 MG's
Length (gun excluded) - 6,8m
Width - 3,7m
Height (to turret roof) - 2,26m
Armour (frontal) - rated as 800mm vs. KE and 1200mm vs. HEAT
Armour (side) - rated as 90mm vs. KE and 450mm vs. HEAT


Externally mounted unmanned turret with autoloader
Crew - 3 men
Combat weight - ~60 metric tons
Engine - MTU 883
Armament - 140mm gun with 34 rounds, 40mm AC with 140 rounds and 2x7,62 MG's


Conventional turret without autoloader
Crew - 4 men
Combat weight - ~60 metric tons
Engine - MTU 883
Armament - 120mm gun with 48 rounds and 2x7,62 MG's


Conventional turret with autoloader
Crew - 3 men
Combat weight - ~35 metric tons
Engine - 1000hp MTU V8
Armament - 140mm gun with 40 rounds and 2x7,62 MG's
Based on CV90


Presumably like T140 but with a 120mm gun


Presumably like T140/40 but with a 120mm gun


Presumably like L140 but with a 120mm gun.
So in essence CV90120.


T140/40 sounds like the one that made it to mockup form.

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According to the construction of its autoloader(if this one really belong to it),I can sure it was 120 gun.

The ATAC(XM291) is quite intreseting but with too less information about it.

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Eh...the URL was disabled...

Sometimes the forum host in particular we use sort of messes up if you image link to an attachment from another site or a URL that ends in something that isn't like .jpg/jpeg, .gif, png, etc (that's not the case here, but regardless, it probably was the attachment thing, I get the same errors linking to attachments on Tiexue for example.)

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Also, while I'm not sure how closely it resembles the above design, Meggitt does actually still manufacture a 120mm autoloader to this day that was originally based on the turret dimensions of the M1 Abrams.



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