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5 hours ago, Collimatrix said:

That's this gun, right?  The super thick walled 105mm smoothbore mounted on the Leo 1.5:

 

QzT658f.jpg

Yes. That tank was called Keiler. There was also a version with the 120mm L44. The interesting characteristic about the Keiler was its power-to-weight ratio. At only 40 tonnes this tank was  carrying the mighty 1500hp engine from the Leo2, resulting in 37.5 hp/t.

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8 hours ago, chebuRUSHka said:

Yes. That tank was called Keiler. There was also a version with the 120mm L44. The interesting characteristic about the Keiler was its power-to-weight ratio. At only 40 tonnes this tank was  carrying the mighty 1500hp engine from the Leo2, resulting in 37.5 hp/t.

It was armed with a 105 mm smoothbore gun and it was powered by the MB 872 Ka-500 engine developping up to 1250 horsepower, the Keiler weighed likely as much as the Leopard 2K prototypes ; between 46 800 kg and 50 500 kg.

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51 minutes ago, chebuRUSHka said:

Like i wrote there were different versions:

Two Keiler prototypes were produced from october 1969 and were trialed in 1970 :

1487792913-leo2-ex.jpg

 

 A total of sixteen Leopard 2K prototypes were produced and tested between 1972 and 1975, seven of them were fitted with a 120 mm smoothbore gun :

1487792920-leo2-proto120-2.jpg

 

24 minutes ago, SH_MM said:

Also note that there is not one Rh 105 gun, the name has been used for various different guns, but not officially for the gun you seem to be interested in.

I would add that this is family of five 105 mm rifled guns, with designations ranging from Rh 105-11 to Rh 105-60.

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35 minutes ago, Xlucine said:

This is all the formula anyone could ever need for APFSDS against homogeneous materials:

http://www.longrods.ch/

All you need is the length and diameter, as the muzzle velocity is given in the chart sovngard posted

Hello, thanks for your reply.

I know that site, but unfortunately there is no formula I'm aware of, which works for all penetrators. There are some formulas which work for modern sabots, but not for sabots from the 60s. Are you sure longrods.ch can handle 60s/early-70s sabots?

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APDS is outside the scope of that equation, but with a L:D ratio greater than 4 willi claims that the equation is accurate. Any APFSDS round ought to be into the hydrodynamic range, barring the weird stuff with tungsten tips and a steel body. If the 105mm gun in question fired non-homogeneous penetrators, then extrapolating from the russian non-eroding APFSDS is your best bet - it should be somewhat applicable to the demarre equations

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1 hour ago, chebuRUSHka said:

Fair enough. For me the Leopard 2K is just a rebrand. I fail to see any substantial difference besides the gun.

Different engine compartment in order to fit the new MB 873 Ka-500 engine (1500 hp) and its HSWL 354 transmission, type 570 tracks instead of the type 635.

On 21/02/2017 at 5:23 PM, chebuRUSHka said:

I was wondering what were the Rh-105 penetration capabilities with 60s and 70s ammo?

I have a table listing the performance of a dozen of APFSDS ammunition against NATO targets at given ranges.

I'll post it later.

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