I believe it was a Brit Challenger I during ODS. Most sources quote the range at 5100m, though there are other references which put it anywhere between 4000m-6000m.
I heard a German Ferdinand made a kill on a T-34 at 4.5 kilometers. Can’t remember exactly. The most impressive “kill” I think I have ever heard was the test shot of the Super Pershing on a Jagdpanzer. Went through the front glacis plate, through the crew compartment, through the entire engine block and out the back. Pretty impressive. The Challenger kill is the longest modern shot I now of.
Digressing slightly from “longest range”, another pretty impressive “kill” was the Iraqi T-72 reported to have been hit by an M1A1 firing through a sand berm to make the kill. Range was inside 1000m IIRC.
well I know it’s not a tank, but I was about five hundred yards from point of impact when “Big Boy” drilled a haystack at 40,000+ yards with a one shot kill. Of course the hay stack blew up for about three minutes afterwards.
Think New Jersey firing at near max range on intell targets. He blew the hay stack, a house. and a bridge over a two hour period. “Big Boy” was the code name for the New Jersey. He was parked to the east of an island off Tam Key, and was firing so far that they were worried about actually clipping a hill top on the way in. I thought they’d flipped their lid shooting at a hay stack till it blew up for what seemed like forever. It took three consecutive hits on the concrete bride before it gave way. So much for concrete piercing fuses! I also saw a 175 gun make hits at 19 miles once. And then there’s the story of a 155 towed howitzer zapping a couple PT 76’s at over 7 miles (I never actually saw this one). One was hit so hard that the hull went up in the air four or five feet (Kam Duc 1968 shooting well into Laos) and came down on it’s side.
There was also supposed to have been a friendly fire hit on a Bradley at over 3 miles in Desert Storm by an M-1 tank in the wee hours of the night.
British Challenger I firing a HESH round, hence the long range. As smoothbore guns don’t fire HESH they won’t match that sort of range with KE rounds.
In ship to ship, a sailing HMS Warspite hit a moving target at +26,000yd
“During the Battle of Calabria she was credited with achieving the longest range gunnery hit from a moving ship to a moving target in history. This was a hit on the Giulio Cesare at a range of approximately 26,000 yards” http://en.wikipedia.org/wiki/HMS_Warspite_(1913)
Scharnhorst hit HMS Glorious at about 24,000yds in 1940, during the invasion of Norway