Bernd 12/12/2019 (Thu) 22:35:44 No.33055 del
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>>33016
>this is why a smoothbore gun was preferred over rifled, as it’d generate less recoil on an already lightweight vehicle

Smoothbores also are some kind of "modern trend" in MBTs, everyone used it from 70-80s. Only Brits still use rifled (but they also have special tea boiler in tank, so their opinion doesn't matter).

First reason is invention of APDS - thin and long projectile that looks like arrow and has best armor penetration. It needs to be very fast, but rifled barrel has some limitation about max speed of projectile. It also can be stabilized by arrow-like fins, so smoothbore is ideal for it.

Another reason is HEAT - projectile that forms hot jet on explosion, and penetrates armor by pressure. HEAT is less powerful than APDS in terms of penetration (mostly because it is easier to create specific anti-HEAT composite armor), but has better damage effect, so it is also widely used. But jets formed from fast rotating round work worse than jets from stabilized round. So, smoothbore gun is also better for this.

Third reason is barrel lifespan and complexity. High pressures require hard alloys, but even special materials couldn't prevent rifled barrel from faster degradation. It is also much easier to produce smoothbore barrel, so it is cheaper overall.