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Tanks of the Commonwealth in WWII thread

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1 hour ago, EnsignExpendable said:

That was quite the roll-out reveal...


I assume that protruding from the turret face is a smoke mortar, which I guess didn't make it to the main production.


On the topic of Rams, is this a 75mm gun pictured? I couldn't find anything on the image.



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29 minutes ago, EnsignExpendable said:

Yup, that's the 2" bomb thrower. I think it got eliminated at some point.


The Ordnance QF 75 mm had a muzzle brake, so I don't think that's it. That also seems to be a Ram I turret. Do you have this photo in a bigger resolution?

That was as big an image of it as I could find, and they were all on pintrest only.


After looking at it again while fully awake, the idea of it being a dummy gun for a an OP vehicle comes to mind. There certainly seems to be a few more bits attached to the tanks exterior.  However, wouldn't those all have been late production vehicles?  This is seems to be an earlier one, especially since I now also notice it has the smoke thrower on the turret face. 

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a dummy gun for sure, probably an early try at a recovery vehicle or work on the early Command OP tank design.


Lots of nice little clips in the newsreels if you look.


Ready for the day


Example of training getting ready for D-Day, shows waterproofed Rams landing from ship on the beach, blowing off the water proofing and then a line of them firing out to sea.

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13 hours ago, EnsignExpendable said:

8:03 shows a neat item, a gun sight added to the machinegun cupola. Before that, the idea was that you would just walk the machinegun onto its target with tracers, which turned out to not really work at all.

Ended up standard for them as far as I know, for whatever reason you hardly ever see it in photos (probably easy to damage or misplace it, so not fitted unless needed)




M6 heavy used the same sort of Idea as well.


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A line drawing I have been cleaning up from the tank's manual.







1 hour ago, Jeeps_Guns_Tanks said:

There are enough around in Canada( I think), someone should measure one, like the Chieftain did with the T29 Heavy tank a few years ago. 

It would change depending on date the hull was cast. They thinned the armour out in some places then thickened it in others at later dates. We just don't know by how much exactly or where in many cases.




Around Hull number 321


"Thickness of metal around turret and cupola opening reduced, also at several other points where such reduction does not come below design or service requirements"



Spring 1942


Increased engine protection Ram II tank
"The armour thickness on the sides of the engine compartment has been increased by the change in hull design. Mr. Jamieson can elaborate."




Possible to find photos that show off well how thick some areas are.















I can almost see the roof around the turret and cupola being 3 inches like some spec sheets seem to indicate when you see photos like this. (would also explain why they thinned these locations out on later tanks)







Compare those to the Sherman Jumbo's roof.






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2 minutes ago, Jeeps_Guns_Tanks said:

Nice work on that image clean up. Having done a few myself now, very clean work, it looks great. 

Thanks, but this one was just mostly removing lines for the image.


Start to finish









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Yes, the armour thickness changed, and also the casting was variable thickness anyway. I like how people confuse the Grizzly and the Ram and write that the Grizzly had 3 inches of front armour. So many books falsely state that the Grizzly was called M4A5, I think the confusion stems from there.


@whelm I write quite a lot about the Ram on Russian sites, may I post the image you cleaned up? I will credit you under whatever name you provide.

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1 hour ago, EnsignExpendable said:

Yes, the armour thickness changed, and also the casting was variable thickness anyway. I like how people confuse the Grizzly and the Ram and write that the Grizzly had 3 inches of front armour. So many books falsely state that the Grizzly was called M4A5, I think the confusion stems from there.


@whelm I write quite a lot about the Ram on Russian sites, may I post the image you cleaned up? I will credit you under whatever name you provide.

Sure you can use it if you like.





Another interesting thing to note on the Ram, most assume It's using M3 medium parts, and well it is and is not.


It used the design as a base but did their own thing with designs from it. This is why the cupola you will notice on the Ram no longer has the vision ports on the side as an example. You may notice the odd M3 in a collection having the same cupola, they are just using a Ram one as they were unable to source an M3 type.


They also thickened them up quite a bit in the casting compared to the standard M3 type. The one spec sheet states 2 1/2 inches (63.5 mm) on the cupola but that may have been for the thinnest area only (rotor shield) A firing test on the Turret front with the 2 and 6 pounder to test shock resistance for the bolts missed the target and a 2pdr AP round struck the cupola penetrating it from the front.


Fired head on from 100 yards and with a striking velocity of 2096 fps, pierced the front but had spent all of it's energy from doing that, as when it hit the inner back wall of the cupola, only displacing the padding around the rim and then fell to the floor.














2 pdr chart from the same period, either the casting was exceptionally good quality or that area was a bit thicker then 63.5mm


Another 2 pounder mistake from the same time frame piercing the hull side. , Canada's pride book on the Ram has a photo of the actual damage from the outside of the hull. I used a cleaned up hull wiring diagram I did to show the rough location, this image is interesting as well as it gives somewhat of an Idea on how and where the casting on the hull sides thin out as you head towards the rear.








Drivers Vision door. It was thicker, by how much ? text is to blurry but when you compare photos of them it's easy to tell the Ram's is a thicker casting.












Another thing most sources get wrong, even the spec sheets and the manual as they only list "aprox" figures for weight. All that armour weighs a ton. In many cases the Ram weighed more then some versions of the M4, I have seen them list it weighed as much as an M4A4 a few times.


Highest value I have seen is from 1944 they state the Ram was fully stowed up to 68,000 lbs when using CDP tracks while testing different bogie materials. But on average I see a listing of about 66,600 lbs stowed.


Battle order weight (fully stowed) comparison






In fact the designers knew the weight was so great that suspension springs were cherry picked that could take a higher load then normal. This was before the improved M4 type suspension with heavier springs came out.

The Ram was a Jumbo before the Jumbo existed.

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I'm actually doing some research on the Sexton right now, and the suspension and running gear are a sore point, specifically synthetic tires. They seem to do a lot better in some conditions, but a lot worse in others. The Sexton also used the Lee style bogeys for a lot longer since it was lighter than the Sherman.

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They may have had plans drawn up for armouring the sexton in the same way as the M10 with temporary plates that could be removed after they were used. Was listed as a desirable feature for a mod. Never was done as far as I know.




in 1944 they talk about a new order being placed for more sextons and how it would be a good time to look at a bit of a redesign.





good breakdown on the weight difference with suspension type and track used.








Apparently one of the Ram books on the development from service publications states a number of Ram hulls were built as ammunition carriers after production on the Ram and the Grizzly had ended, well into sexton production. So they either converted existing stock into that at the factory or had spare hull tops laying around for use.


This was around when the three piece lower front was phasing out on the sextons and the single piece being used, so the Ammo carriers may have been built with those. Could explain why 1944 and on they make a note to point out the ground clearance on the Ram when it's using a single piece front compared to a 3 piece one.

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2 hours ago, EnsignExpendable said:

Which book, Canada's Pride or one of the minor ones?

One of the smaller development books. Someone on the maple leaf up forums posted that I can't confirm as I don't have copies on hand.

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production end on Ram II gun tank at CT 160193

production ended on Grizzly at CT 164012

production ended for Ram OP tanks at CT 205181


Book apparently claims the late ammo carriers were CT 231070-CT 231097

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