Hello good dopers.
Reading through an old, 2002, edition of Jane’s Warships I came across the Sariwon/Tral class,(Tral being the original Russian class, Sariwon the lead ship in N.K.)
Main armament an 85mm/T52 Tank turret?
So many questions!
Can you fully protect a Tank turret against the Sea,
Stabilization at sea/land,
Tank ammo is designed for a specific purpose, ie destroying other Tanks. The logic of using the ship against amphibious tanks very quickly passed me by.
I’ve read that during the Allies large scale amphib. operations in WW2 that Tanks, Howitzers and Self Propelled Guns were used as sure bombardment but subsequently sent on shore to support the troops but tese Turrets are fully integrated into Corvette, type no.s 513, 671 & 725. Author, Robert Hutchinson has doubts about last penant number.
Even if it’s not quite the perfect tool for the job, there’s a lot to be said for using the same off-the-shelf hardware for many different applications. You get a better price for buying in bulk, you can use the same mechanics who are trained on the tank turrets to maintain the ship turrets, you can transition more flexibly if what you need from your military changes. And really, the needs of a tank and of a warship aren’t all that different: In either case, your goal is to make holes in other vehicles, possibly armored.
There’s a whole variety of tank ammo, discarding sabot rounds are only one type. (And would damage a boat, though I’d rather use HE)
Protecting the gun from salt spray is the same whether it’s a tank or not, and stabilizing a ship gun is more similar to stabilizing a tank gun than an artillery piece or mortar tube.
So all in all, it’s a perfectly useable idea, in my opinion.
I cannot see much use for it in a maritime application, the muzzle velocity for a tank shell is much too low for any useful range - tank rounds are not designed to penetrate armour at ranges exceeding 5 miles or so.
They might be useful for something like a small fishery protection, anti piracy role etc where there is no expectation of coming across another warship - simply not enough range for a naval engagement
This seems to be for a North Korean patrol boat. North Korea doesn’t have a blue-water navy, it has a couple of patrol boats whose job would be to sink merchant ships and smugglers and pirates, or maybe do some light shore bombardment. If they run across a warship or airplane from a real navy they’re dead.
They probably had a supply of these cannons and just welded onto an old boat the Russians sold them for scrap prices. Much cheaper than a purpose built system, and good enough for the limited role the ship is intended for.
In one sense you are correct. A purpose build ship turret and gun would be more practical and deadly at sea. However, if you already have the armored turrets and a bazillion rounds of ammo to go with them, then to save money you can weld it onto a ship. This is a very economical way to get combat ships you could not normally afford.
Also I want to point out that tanks are usually designed to combat not just other tanks but any other targets they run into so they usually carry armor piercing, high explosive, smoke, and other types of ammunition. You are mistaken when you say, “Tank ammo is designed for a specific purpose, ie destroying other Tanks”
Protecting the turrets from the sea is also very possible by using the right kind of paint and keeping your seamen busy maintaining the hardware. At sea sailors are always kept busy with this kind of work, always.
Stabilizing firing a gun at sea is ALWAYS a problem on any warship and you are correct to believe a purpose built gun turret would be better, but on calmer waters you will be okay at sea with a tank turret.
During World War II when lots of nations had to make do and jimmy-rig whatever weapons they could all kinds of less efficient weapon systems were used. Just to have a glimpse of a ship turret that was put on a tank look at this website:
This tank body with a ship turret was not too great for reasons you might easily guess at, but it did put a very powerful gun on a mobile carriage and your enemies would be right to fear this weapon.
The barrel is usually, but not always, longer on a ship’s gun, than a tank’s. Compare the 120 mm Rheinmetall gun on the M1A1 Abrams MBT to the 5in/54 gun on U.S. warships. (Yes, 120 mm is slightly smaller in diameter than 5 inches.) The 120 mm’s barrel is either 44 or 55 calibers long. The 54 in 5in/54 refers to the barrel length being 54 calibers long. It’s been extended in the 5 in/62 modification. Longer barrels mean higher muzzle velocities, all else remaining equal.
Perhaps a better comparison is between the 76mm F-34 gun used on the T-34 and the 76mm OTO-Melara naval gun? The F-34 has a barrel length somewhere in the 42.5 calibers range. Or 3.162 m. It fired a 6.23 kg HE shell at 680 m/s. The OTO has a barrel of 62 calibers and 4.72 m in length. It fires a 6.3 kg HE shell at 905 m/s. So, same shell, but about a third again as fast.
Both naval guns and tank guns fire a high-velocity, high-pressure projectile. Usually in direct fire, and with gun elevations below 45 degrees, unless targeting aircraft. (The other purpose in the Dual-Purpose 5 inch naval gun) Howitzers, OTOH, fire a lower velocity projectile, from a shorter barrel, usually on an indirect flight path, I.e,. with over 45 degrees of gun elevation. There, the attempt is to fire a heavier projectile over an obstacle (like a wall) than would be practical with a rifled gun. IIRC, barrel life is also a great deal higher with howitzers than guns. I’m not sure what the difference is between howitzers and some of the larger mortars. Breech-fed vs muzzle fed comes to mind, but aren’t some of the larger mortars also breech fed?
As to effective range, I wonder if anyone’s done any naval testing with the 120 mm of the Abrams? The range of the DU sabot round is absolutely ridiculous. If this reference is correct, something like 70 miles at max elevation. It sounds like it would utterly stomp any extant naval armor, especially since no one does the battleship thing anymore.
Per Stinky Pete’s post, another semi-naval turret adapted to tanks, was the M42 “Duster” AAA vehicle, mounting a twin Bofors 40mm gunsystem. It was reputedly quite effective against ground targets. I don’t know whether the M1 40mm on the Duster was the same as on so many ships during WW2.
In the movie PT109 they showed them mounting an anti-tank gun to the ship prior to their last mission. Wikipedia says this actually happened and that the timbers used to strap it to the boat saved lives by providing flotation devices for the men to rest on.
Hmm I’m curious and very dubious of this re the 5 inch 54 calibre guns.
‘there is also a new guided round that is supposed to be able to destroy maneuvering anti-ship missiles’.
Yes, I realize there is ‘some’ hyperbole, no pun intended, but I still can’t see any advantage to a 85mm gun, with no over the horizon capability and no OTHR direction or radar.
Jane’s give a standard, would give! in fact I can’t find the USSR using 85mm, apart from as from an anti tank gun in the D48 Anti-tank gun…
I’ve heard of very large calibre guns being used in aircraft, esp. the c130 with a 100mm + gun but no turret.
Was, is, the North Korean Navy, properly: The Korean People’s Army Naval Force, actually any form of credible force. Certainly in the Littorral area which is their 200km rule, and no I haven’t read the various armistices, they not a blue water navy.
I do wonder whether their Navy is designed to stop emigration rather than invasion
The N.K. Army and Airforce is a very different matter.
Peter
Some tank guns have been adopted for naval ships. I can think of the soviet 135mm MBT gun (never mounted on a real tank) adopted for the Kirov/Frunz crusiers. The mount and armor by then was of course different from what you’d have in a main battle tank.
OTO-Melara has been going on and on about a guided subprojectile concept with their 127mm gun. They’re talking about getting the electronics down to fit into shells for the 76mm I mentioned above. When I say guided, I mean GPS, with possibly a radar terminal seeker loaded with a picture of the target. Basically, a replacement for a very small smart bomb, like the USAF’s SMB concept, but even smaller. Lob the bomb very high, then let it glide to the target via large pop out wings.
They do mention possibly adding semi-active laser homing to the shell, or, what a smart bomb does. This has been done for awhile, see the M712 Copperhead, but getting it down to 76mm will be a feat. As will giving it enough command authority to guide it to an approaching sea-skimmer. Can a modern LIDAR designate a fast-moving target that far away? Why not though? Especially given Moore’s Law?
The 85mm gun was used because they had them. I wouldn’t look any deeper than that. More than effective in the 50s against small boats, or other non-missile armed small combatants. Not so much against a radar-directed auto cannon with a 60 RPM firing rate, but those are the breaks. As to their Navy, I couldn’t comment, except that I don’t think a corvette would be their first line of defense.
I think the USAF has gotten rid of the 105mm howitzer used in the AC-130 mods, but I’m not sure. I had no idea the 135mm gun originated out of a MBT design. Ignorance fought.
I have to add: the 135 mm was never realized in a tank but a 130mm was built as a towed artillery howitzer, the M-46. This was translated into the AK-130 naval gun. The shells used in the AK-130 system are compatible.
The SU-85, T-44, KV-85, and IS-85/IS-1, but the T-34/85 was by far the most numerous and North Korea has a lot of them lying around from the Korean War era.
The 85mm was adapted for use as tank gun from its original use as an AA weapon, the 85mm M-1939 (52-K).
A gun is a gun is a gun. The big differance between the design of a tank gun and a naval gun is weight. A ship can carry far more weight than a motorized land vehicle. Longer barrels, heavier armor, more ammo. Designing a barbette or bolting/welding a gun originally designed for tanks or anti-aircraft defense to a large ship should present few weight or balance problems. Try mounting a battleship’s 250,000+lbs, 16"/50 caliber Mark 7 gun to a land vehicle that doesn’t run on railroad tracks.
Paint, lubricants, and elbow grease protect steel ships from salt water. (If it moves, salute it, if it doesn’t move, paint it.)
The 85 mm (3.34 in) guns various projectiles could be used against any unarmed ship, ships with simlilar or smaller guns, harbor or land targets within the range of the gun/projectile (heavier projectiles have shorter ranges).
The shell’s case, propellent, and ignition system would be similar. The projectiles could be armor percing, high-explosive, anti-personel, smoke, gas, biological, or whatever the designers wanted to shoot at the enemy.
I am not a ballistics expert, but if I recall correctly, velocity of a shell falls off fairly rapidly at long range. Heavier shells (like the good old fashioned 16inchers) retain their energy better, but a 120mm shell aint that heavy, for these purposes.