Uncle-Heavy
This could be really promising 
This could be really promising
There are so many Leo2s that I’m thinking about… Swedish Strv and Canadian w barracuda would be my favorites.
Mario
Just when I stopped buying kits because nothing else interesting was coming along this gets announced.
Looks like I will have to buy one more Leo kit 
Leo 2’s get the Rye Field treatment? This is going to make a lot of people VERY happy! 
That Leopard 2a6m CAN looks promising… But come on if you doing a Canadian kitty, please mold on the Barracuda!
Let’s GOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO
Whelp! Looks like a Leo 2 is in my future builds
I put it on my wish list. You just can’t have enough Leos … 
Great Dio though …
The tank would swing backwards with the velocity of 0.2 m/s
55 tons of tank firing a 7.3 kg projectile at 1600 m/s.
Other ammo types have heavier projectiles and a lower muzzle velocity.
I think we can safely assume that the tank will not swing faster than 0.5 m/s for any type of ammo
Ammo types:
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Hay Robin, is that allowing for a cross wind?
Also, further variant to include would be the Trophy APS version… But that may be too new.
Cross wind has not been considered.
A strong head wind might actually influence the tank more due to wind pressure against all those vertical surfaces …
The tank would swing back, break/damage both boom arms and possibly some suspension arms/track when it lands. While not worth the cost, I would still like to see it and I agree with @Johnnych01 it would be a great looking diorama.
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ummmmmm …
The impulse from the projectile leaving the gun would push the tank back at the speed of 0.2 m/s (or 0.66 ft/s).
This speed for a pendulum equates to a total swing height of 0.2 cm (0.0002 meters or 1/100 inch)
The pendulum arms are roughly equal to the length of the Leo 2A4 or 7.7 meters
Using the arccos function we get the swing angle to be 0.13 degrees and the swing distance will be 0.018 meters (18 mm, 0.7 inch)
If we go for really big margins and assume that the speed given to the tank would be as high as 1 meter/second we get the total lift height of that pendulum to be 5 cm (1/5 inch)
This would give us a swing angle as arccos (765/770) = 6.5 degrees, the traveled distance before the tank starts swinging back would be 87 cm.
Going from nothing to 1000 mm/s would cause concussion and possibly other internal damages to the crew. Not gonna happen
I doubt that such a limited swing would cause things to topple or break.
The overestimation of going for 1 m/s is huge, the likely value is 0.2 m/s.
The calculation furthermore assumes that the force from pushing the projectile out of the barrel is translated directly to the tank without any dampening
“The gun’s recoil mechanism is composed of two hydraulic retarders and a hydropneumatic assembly.[4]”
I don’t know how much recoil force the dampers absorb but the dampers will sooner or later transfer the energy to the tank so I think the dampers can be more or less ignored.
If they take 20% of the recoil force away the total swing angle would go down to 0.1 degrees which is a 19% reduction in swing angle, basically from extremely close to nothing to 81% of extremely close to nothing. The swing distance would be reduced to 1.6 mm or 0.065 inches
Edited: I realised I made a fatal mistake in the original calculations, they have now been revised
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I’m getting some nasty flashbacks to grade 12 physics here
Humans and sudden accelerations.
My line of work is to compile vibration risk analyses, primarily for rock blasting but also for other vibration sources.
Safe limits for a buildings are typically between 20 mm/s and 80 mm/s. This may seem to be a lot of movement BUT the movement only lasts for 1/160th of a second when it is caused by rock blasting
so the actual distances traveled are on the level of a human hairs thickness.
We usually set the limit at 70 mm/s for a wooden building since we don’t want to subject any tiled walls to too much shock.
The vibration speeds that actually cause proven damage are upwards of 100 mm/s, usually at the 200 mm/s level.
We humans react to vibrations on the level of 0.3 to 0.5 mm/s. The typical inhabitant of a brick building will thus react to a vibration which is 1/100th of the official safe limit for the building.
Colleagues who have experienced 70 mm/s say that they almost sh*t themselves, when we start hitting 200 mm/s it gets really scary, people can act confused and dazed afterwards.
Alrighty then, where does this bring us?
200 mm/s = 20 cm/s = 0.2 m/s
My calculations in the previous post said that the maximum speed would be in the 0.2 m/s range.
Presumably less.
The diatribe in this post aims at explaining why someone sitting inside a tank when the main gun fires may think that it feels as if the whole tank moved sideways a foot or so.
It didn’t, it moved a smallish fraction of an inch. It feels like it jumped but that is only because we humans are so dang sensitive.
Dennis: Please accept my apologies if I revived some high school trauma 
I will trust your math. On a M1, if your head is outside the hatch when firing you can get a bloody nose, happened to a number of M60 TC’s who tried the same technique. All the force is anchored with a 70ton vehicle, now with tank suspended all the force goes to the cables and boom. My thought was those booms can do ok up and down but side motion is more difficult to handle especially at 70t.
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Head outside of hatch will expose you to the blast wave.
Most of the pressure wave will go forward but I have no problems accepting that
a lot of it spreads in other directions so I can imagine that it will be sufficient to cause
a sudden and totally unexpected nose bleed.
If the nose is too close to the hatch frame I suspect that a sudden impact might be in the cards as well.
Even if the tank itself doesn’t rock more than an inch the flexibility of the human torso could allow the head to snap forward enough to whack a nose.
They do rock a little on the suspension and the blast wave raises a lot of dust:
You could hide behind a berm or in a wide ditch, haul the tank up, fire and lower the tank back down. A Rube Goldberg solution.
Kodiak announced by Border… AEV 3
A colleague told me about his time in Swedish compulsory military service.
His unit was a 120 mm (4.72 inch) mortar company.
One of the loaders in his platoon had tried getting out of the exercise due to a severely blocked nose , sinuses blocked, the whole shebang.
They were shooting rapid fire so one loader dropped a grenade in while the other held his grenade at the ready beside the barrel. First shot went off with the muzzle two feet from his head.
The blockage in his sinuses was blasted all over the place, instant sinus deblocking …
Just had a little leak… 
I have to trust Robins Math’s as
However I do understand and also agree with what your saying Ryan…
A factor has to be the friction of the tank firing from a static firing point hard standing and it’s 70 ton weight. Also the fact that the driver will be in situ with the handbrake applied or the foot brake if he is on a fire and manoeuvre shoot.
I have seen a Chally 1 roll back about 2 to 3 feet on firing when said dumba*s driver forget to apply the handbrake. The only reason it stopped was track friction on the hard standing and the driver waking up and using foot brake.
I also think (although I don’t know why or how) the turret over the side will have an effect with stability as a 100% stable gun platform on a tank is firing gun front or gun rear…
Does anyone know of any manufacturers make the Bergepanzer BPz3 in 1/72 ?
