2S4 Tulip.

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"I have actually seen 12 240 mm mortars in action together. These fire not 16 kilogramm [about 35 pounds] but 100 kilogramme [about 220 pounds] bombs. Within twenty minutes, each mortar fired 15 bombs. This represented as I later calculated, a total of 18 tons of explosives and cast-iron splinters. I found the noise absolutely staggering. It was amazing that men could retain their sanity in the midst of it. While the firing was in progress, on had the impression that the thousands of tons of explosive were going off each second and the whole process seemed an age. The astonishing destructive power of these mortars makes up for any inaccuracy in aiming or in dispersion. I believe that the this is the correct approach." - Suvorov.

"Putin's 'Beasts of War' Wreak Havoc in Ukraine; Why Russia Deployed Tyulpan [2S4 Tulip] Mortar at Frontline"

Go see the video courtesy You Tube:

"The second phase of Russia's war in Ukraine has been marked by heavy artillery, Lancet drones and aviation attacks. Russia has deployed its heaviest artillery at the frontline, which delivers devastating strikes on the Ukrainian units stationed at Donetsk and Krasny Liman directions. Russia's artillery back-up in these zones is the 2S4 Tyulpan 240 MM self-propelled mortar."

Further from Suvorov:

"The outstanding simplicity, reliability and ease of maintenance of the 240 mm mortar are vital qualities, and they played a decisive role when the moment came to decide which should be the first artillery weapon to fire nuclear projectiles."

Read the wiki entry Viktor Suvorov. Nom de plume of Vladimir Rezun the controversial Soviet era defector.

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