[Would you like to see this in-game?]
TL;DR: An SPG based on an elongated ZBL-08 chassis equipped with a new 125mm cannon that has a 60:1 length to caliber ratio.
On June 10, 2015, the 127th Ordinance Institute, of the Central Northern University, handed over a brand new 125mm multipurpose cannon to the PLA. This cannon had a length to caliber ratio of 60:1. For comparison, the German Rh 120 L/55 has a length to caliber ratio of 55:1. The Institute claimed that this new cannon would have the highest range, velocity, and penetration power of any 120mm/125mm cannon in the world. The claimed velocity of its APFSDS round is a beefy 2000m/s. This is achieved through the use of larger, single-piece cartridge, which allows for a greater amount of propellant and a longer APFSDS rod. When the new 125mm cannon was first spotted, it was in a towed configuration, however, the recoil hydraulics are placed in a fashion that optimizes reduction of horizonal recoil, suggesting that it was meant for direct fire. The recoil hydraulics are are attached directly to the top of the breech block. Due to this, firing at higher elevations could damage the recoil system. As previously mentioned, the PLA took possession of the new weapon, taking it to a testing facility and by the 14th of June, only four days after it has been accepted, all mention of the weapon was scrubbed from the Central Northern University’s website. The gun simply disappeared from public view until some time in 2016 when a peculiar vehicle was spotted. This vehicle had the chassis of the ZBL-08, however, it appeared to have been elongated. The turret of this vehicle appeared to be a modified PLL-09 turret and in said turret was the 125mm cannon that the PLA had taken just a year prior. As of right now, this vehicle does not seem to have an official name, so it will be henceforth referred to as the ZBL-08 125mm SPG. It is unknown if this vehicle retains the amphibious nature of the rest of the ZBL-08 family, however, due to the added weight, this seems unlikely.
Place In War Thunder:
China excels when it comes to armored car-based weaponry, producing variants upon variants of their vehicles. A 125mm cannon, that’s longer than the mighty L/55, mounted on a very mobile chassis is very sure to attract some attention to the Chinese tech tree. The playstyle of this vehicle would be very similar to most other 8x8 armored cars at high tier. Your mobility would allow you to take up advantageous early game positions and lay into the sides of unaware MBTs. Hell, depending on the performance of the APFSDS, flanking might not even be necessary as you might just be able to tear through the front of whatever you encounter. This firepower does come at the cost of survivability, however, as your light armor makes you a prime target for CAS and autocannon carriers. The reload of the ZBL-08 125mm SPG would likely also not be competitive as large and long single piece ammunition is difficult to load in enclosed spaces. I think this vehicle would make the perfect continuation for China’s tank destroyer line.
Armament: 125mm cannon
Dimensions: 8.0m, 3.0m, 3.0m (L,W,H) (Dimensions of the PLL-09. This vehicle is longer.)
Weight: 24000~kg (est.)
Armor: Same as ZLT-11 in-game.
Crew: At least 3 (Commander, Gunner, Driver, and possibly a Loader)
Ammunition: APFSDS and likely some sort of HE.
Speed: 100kph (Possibly slower)
The new 125mm cannon in a towed configuration (Notice how the recoil hydraulics are placed):
Front View of the 125mm cannon in a towed configuration (You can also see the new longer cartridge):
The 125mm cannon at maximum elevation (If fired at this elevation, the recoil hydraulics would be severely damaged):
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