New Indian light tank being developed: 25 tons and with a 105 mm rifled gun.

 https://www.overtdefense.com/2022/10/28/defexpo-2022-drdo-light-tank-showcased-planned-features-revealed/

Thats an interesting development, but makes sense as a lighter tank may be needed to get up to the very austere areas in the Himalayas where they are squaring off against China. 

China's Type 15 light tank was debuted a few years ago, designed for specific use at high altitudes near Tibet and India. In addition to weight, premiums were placed on the ability to work in high altitude, low oxygen

https://nationalinterest.org/blog/reboot/chinas-type-15-tank-ready-fight-india-war-179570

Chinas Type 15 also uses a 105mm cannon. However it uses what looks to be a quite long penetrator compared to its western counterparts?

https://www.china-arms.com/2020/07/15-tank-autoloader-apfsds/

EmericD said:

Initial tests have shown that against fortifications, 3 rounds of 40 mm CTAI are roughly equivalent of 1 round of 105 mm (the low pressure gun of the AMX-10 RC)

Is this in terms of penetrating a fortification, or collapsing / destroying it? 

gatnerd said:

Thats an interesting development, but makes sense as a lighter tank may be needed to get up to the very austere areas in the Himalayas where they are squaring off against China. 

China's Type 15 light tank was debuted a few years ago, designed for specific use at high altitudes near Tibet and India. In addition to weight, premiums were placed on the ability to work in high altitude, low oxygen

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I think I would rather trust the Israeli or Russian options, if I were an Indian tanker.

gatnerd said:

Is this in terms of penetrating a fortification, or collapsing / destroying it? 

Opening holes in walls.

gatnerd said:

-> The 100mm will provide the air blast of 14.7x 40mm going off at once, making it far more likely to be able to collapse a room/ building / fortification.

True.
But it is very unlikely that a field fortification or bunker will be collapsed by under 2 kg going on its outside. Field fortifications and bunkers are designed to withstand overpressure. This is why BDM work by penetrating into the bunker and going off in the inside. Either by KE or by tandem warhead designs.

Civillian structures on the other hand have a good chance of being collapsed or at the very least seriously damaged. Which IMHO is part of the problem. It makes such ammo dangerous to use. Unless you are very sure that there are no civillians left in the structure and no friendlies allready have entered or are close by you can not safely use such ammo.

Time fused ammo for ACs does the trick of penetrating into a bunker or structure and going off inside mostly causing effect against the occupants and not the structure itself. Which IMHO makes it far more effective in this role.

Will be intresting to see if it materialises and if it does how well executed.

gatnerd said:

Thats an interesting development, but makes sense as a lighter tank may be needed to get up to the very austere areas in the Himalayas where they are squaring off against China

Not only China. Pakistan as well.
For India such a AFV makes a lot of sense. Limited resources and infrastructure. It also will most likely not face 3rd gen or later MBTs so the 105 is a very sensible choice to duel with its kin.
Allthough the ATGM plus AC combo would work for it as well.

gatnerd said:

Elbit makes the ideal, a AMP style programable HE shell...

FYI.  (See 2:10-2:18)

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