Super Cannon Thread

[CalBear]

When this sort of thing is discussed it is really critical to be clear about what sort of "gun" is under discussion the difference between types in night and day.

As an example the M115 203 Howitzer tips the scales at ~32,000 pounds, the 203mm M1 GUN is just under 70,000 pounds. The M1 155mm gun is 30,600 pounds while the M114 155mm howitzer is 12,300 pounds. You also have the U.S. 4.2" (107mm) Mortar that is man portable. The Germans had a 38cm (15") Mortar that was less than 3,500 pounds.

Most SP "guns" are actually howiters.

 

[Captain Homicide]

Most SP "guns" are actually howiters.

What’s the difference between an artillery gun and a howitzer?

 

[CV12Hornet]

What’s the difference between an artillery gun and a howitzer?

Howitzers have a shorter barrel than guns - the contemporary US Army weapons were an L/23 and L/45 weapon, respectively - and thus have lower muzzle velocity and fire at higher elevations. The M1 gun had a muzzle velocity of 2800 ft/second and the M1 howitzer 1850. Range is 23.7km than the gun and 14.6km for the howitzer. Howitzers also, in WW2 use, utilized multiple propellant charges vice one for guns, leading to higher rates of fire due to lighter charges to be loaded.

WW2 was the last war where a distinction was made between the two types. Postwar artillery has largely merged the characteristics of the two into one weapon.

 

[CalBear]

Howitzers tend to be relatively short barrelled, have a higher firing trajectory, shorter range and have some limited utility against reverse slope targets compared to "guns/cannons".

Guns have a higher velocity a much flatter trajectory and are more accurate , to the degree that they can be used to strike specific vehicle or building with aimed fire. (tanks are usually armed with guns, SP guns usually Howitzers).

Mortars are very high trajectory, relatively short ranged low pressure weapon.

To make it even more fun, modern howitzers have mutates to cover a not of both the "Gun/Cannon" and traditional Howitzer role. Tank guns are the only routinely deployed high velocity large caliber weapons on the modern battlefield.

 

[Carl Schwamberger]

WW2 was the last war where a distinction was made between the two types. Postwar artillery has largely merged the characteristics of the two into one weapon.

The last 'gun' in the US arsenal I can recall was the 175mm M107 cannon of the 1950s 1960s era. They were discarded in the 1970s, possibly turned over the ARVN. The intel briefs on the Soviet or Warsaw Pact armies referred to a variety of 100 & 130 and larger guns still fielded.

]To make it even more fun, modern howitzers have mutates to cover a not of both the "Gun/Cannon" and traditional Howitzer role.

Re: the M198 & M177 155mm cannon.

Note the beast loading the 45kg projectile. Ordinarily two men lift it on a loading tray & a third rams it. The M198 is a eight ton brute, very rugged and simple to maintain.

The M777 fires the same ammunition with similar ballistics characteristics as the M198. Its about 40% lighter & a bit more complex with more mechanical assists.

Both cannon have a range of 18km with conventional rounds/propellants & can reach well past 24k with supercharge propellants or base bleed projectiles. Although they have similar or longer ranges as WWII era US 155mm 'guns' they are capable of high angle fires, above 800 mil (45 degrees) and have a wide variety of propellant charge increments..

 

[Reggieperrin]

Just asking some questions for my timeline about really big cannons in a WW2 environment.

Would you count a 380mm rocket mortar as a really big cannon? It’s the biggest thing I know of that was mobile in a tactical sense. https://en.wikipedia.org/wiki/Sturmtiger?wprov=sfti1

 

[EagleKeeper]

American artillery was developed in 'Families' in each family a gun and a howitzer were developed using the same mount and recoil system. The howitzer provided a heavier throw weight at a higher angle while the gun hefted a lighter weight to a longer range. The light family was the 3" gun and the 105mm howitzer. The medium family used the 4.7" (120mm) gun and the 155 mm howitzer. The medium heavy family was the 155mm gun and the 8" (203mm) Howitzer. The heavy family was the 8" gun and the 240mm.

The T92 and T93 were attempts to develop self propelled versions of the Heavy family to support the 'modern' high speed mechanized army. They used a heavy tank chassis because that is what was needed to support such a large weapon. There was no real armor on the vehicle. The army decided that there was little use in this family of weapons and concentrated on the Medium Heavy family for mechinization given the existing powertrains available. These were initially the M40/M43 family based on widened M4 medium chassis with HVSS suspension. In the post war era these were developed into the M53/55 series based on a modified M47 tank chassis.

The 'Atomic Cannon was a 'special' development program at the timw 280mm (11") was as small as they could anticipate an atomic shel being made. So the vehicle that could transport and deploy such a weapon was developed. The duel ended system was adopted to allow it to maneuver down existing European roads and te tight turning radius of roads in cities and forest areas. It was a very maneuverable platd=form and could be deployed quickly. Once atomic rounds could be shrunk to 8" rounds and later 155mm and 175mm there was little need for such large vehicles as the existing 'medium heavy' batteries could fire the rounds.

 

[CaptainCalvert]

The French developed the Schneider 194GPF and TR280 SP tracked guns in WW1 and these were still around in WW2. Some captured 194GPF were reportedly used against the Soviets.
Though mobile, they were slow and unarmoured, so unsuitable for working directly with armoured formations.

 

[Denv2]

Thanks for the interest in the thread everyone

@RamscoopRaider good points. I was thinking instead of 2 big engines working at 50% rather than 2 smaller engines. I was perhaps curious if going easier on each engine and having them run further under their maximum capacity would reduce the chances of a breakdown. Those other factors sound like they would play a large part though and avoiding this would give a pretty reliable vehicle.

I was thinking of using those enormous guns for defensive installations really for the extra range and for the offensive situations I was imagining using it to break a Maginot Line style defensive line in the mountains, perhaps with Flak Towers mixed in at key points. I could certainly have smaller guns in use for both though. Railway guns seem good. Do you have more information on those hyper velocity guns in WW2?

@Jimbo808 @HexWargamer @RamscoopRaider so the super artillery is more for specific targets but not for tank combat. How about for shelling a stretch of front line which has stayed stuck at a location for a prolonged period?

@Pelranius what niche scenarios in Taiwan and in the Korea would require a large gun rather than a SRBM?

@Carl Schwamberger good point, high up guns can see further. On that subject I had an idea before in my timeline for something called a Thunder Tower. Something like a flak tower with guns to attack ground targets rather than specializing in air. What kind of guns would be good on that tower?

@CalBear @Captain Homicide @CV12Hornet @Carl Schwamberger @Reggieperrin those are all pretty good definitions. I suppose we can talk about all kinds of guns on this thread. I suppose a 380mm rocket mortar is an interesting subject. What were you interested in discussing for that?

@EagleKeeper @CaptainCalvert good points. Will note that.

 

[Carl Schwamberger]

@Carl Schwamberger good point, high up guns can see further. On that subject I had an idea before in my timeline for something called a Thunder Tower. Something like a flak tower with guns to attack ground targets rather than specializing in air. What kind of guns would be good on that tower?

In 1945 the Germans used their FLAK towers vs ground targets. Those had cannon up to 88mm or 128mm (?) caliber.

Fortifications often place the turreted or casemented cannon on elevated terrain, which accomplishes the same thing as a tower. In the case of the French the cannon were 75mm & 120mmm caliber.

 

[Denv2]

@Carl Schwamberger sounds good. Noted the gun calibers, thanks for that. Could a variant of a FLAK tower be made with more gun slits down the sides to allow more gunfire at the ground units below? The fortress things seems to be a better way of doing it, I suppose they could use the fortress guns for defense but use a Flak Tower when the ground is very flat to make an artificially elevated position, or in some cases but a FLAK tower to get an even more elevated position for areas of particularly high importance.

I heard that in the late 40s some 8 Inch guns were given auto loaders. Could a double gun turret with something like this be used for coastal defense, perhaps with one auto loader per gun? Would it be worth having flak shells for this to fight of aircraft with the rest of the surrounding air defenses?

Would it be possible to use an auto loader on even bigger ship cannons to help out the sailors?

 

[Pelranius]

Thanks for the interest in the thread everyone

@RamscoopRaider good points. I was thinking instead of 2 big engines working at 50% rather than 2 smaller engines. I was perhaps curious if going easier on each engine and having them run further under their maximum capacity would reduce the chances of a breakdown. Those other factors sound like they would play a large part though and avoiding this would give a pretty reliable vehicle.

I was thinking of using those enormous guns for defensive installations really for the extra range and for the offensive situations I was imagining using it to break a Maginot Line style defensive line in the mountains, perhaps with Flak Towers mixed in at key points. I could certainly have smaller guns in use for both though. Railway guns seem good. Do you have more information on those hyper velocity guns in WW2?

@Jimbo808 @HexWargamer @RamscoopRaider so the super artillery is more for specific targets but not for tank combat. How about for shelling a stretch of front line which has stayed stuck at a location for a prolonged period?

@Pelranius what niche scenarios in Taiwan and in the Korea would require a large gun rather than a SRBM?

@Carl Schwamberger good point, high up guns can see further. On that subject I had an idea before in my timeline for something called a Thunder Tower. Something like a flak tower with guns to attack ground targets rather than specializing in air. What kind of guns would be good on that tower?

@CalBear @Captain Homicide @CV12Hornet @Carl Schwamberger @Reggieperrin those are all pretty good definitions. I suppose we can talk about all kinds of guns on this thread. I suppose a 380mm rocket mortar is an interesting subject. What were you interested in discussing for that?

@EagleKeeper @CaptainCalvert good points. Will note that.

Constant bombardment of fixed targets like logistic nodes (i.e. ports and airports), harassment target of tactical units (companies, battalion HQs), etc.

 

[Carl Schwamberger]

@Carl Schwamberger sounds good. Noted the gun calibers, thanks for that. Could a variant of a FLAK tower be made with more gun slits down the sides to allow more gunfire at the ground units below? The fortress things seems to be a better way of doing it, I suppose they could use the fortress guns for defense but use a Flak Tower when the ground is very flat to make an artificially elevated position, or in some cases but a FLAK tower to get an even more elevated position for areas of particularly high importance.

What you are talking about are modern 20th Century fortresses. They do ok when integrated with a conventional field army. But, often in the 20th Century the field forces were defeated and driven away, leaving the CORF forts of the Maginot Line, the German FLAK towers, the Italian beach & port defenses, ect... isolated and quickly neutralized.

I heard that in the late 40s some 8 Inch guns were given auto loaders. Could a double gun turret with something like this be used for coastal defense, perhaps with one auto loader per gun? Would it be worth having flak shells for this to fight of aircraft with the rest of the surrounding air defenses?

Would it be possible to use an auto loader on even bigger ship cannons to help out the sailors?

In both cases auto loaders or mechanical assists were used. There was still the limit of industrial capacity to build that sort of complex and very robust machinery. So, the most complete systems were on ships. The French CORF worked were heavily automated, tho the projectiles were 75 & 120 mm caliber. Anytime you are loading projectiles weighing 100kg or more mechanical assist is essential to keeping RoF at useful levels. The 6" gun turrets of the US cruisers were some of the most automated of the mid century.

 

[Carl Schwamberger]

@Jimbo808 @HexWargamer @RamscoopRaider so the super artillery is more for specific targets but not for tank combat. How about for shelling a stretch of front line which has stayed stuck at a location for a prolonged period?

Yes. Thats where the US Army in WWII used its large 8" howitzers and heavy long guns. The 155, 203, & 240 mm cannon. The German mountainside trench systems in italy and the West Wall were hammered by those. The preference was to use the six & eight inch long range guns to hit deep targets, but they were used vs heavily prepared defenses.

 

[CalBear]

@Carl Schwamberger sounds good. Noted the gun calibers, thanks for that. Could a variant of a FLAK tower be made with more gun slits down the sides to allow more gunfire at the ground units below? The fortress things seems to be a better way of doing it, I suppose they could use the fortress guns for defense but use a Flak Tower when the ground is very flat to make an artificially elevated position, or in some cases but a FLAK tower to get an even more elevated position for areas of particularly high importance.

I heard that in the late 40s some 8 Inch guns were given auto loaders. Could a double gun turret with something like this be used for coastal defense, perhaps with one auto loader per gun? Would it be worth having flak shells for this to fight of aircraft with the rest of the surrounding air defenses?

Would it be possible to use an auto loader on even bigger ship cannons to help out the sailors?

Those were on the Des Moines class cruisers.

Those weren't "cannon" but naval rifles/guns.

Different weapons that use the same description as far as size. Guns tend to be vastly more accurate, often have longer range, but also tend to have less shrapnel effect than from Cannon/Howitzers and much less than from mortars (which use the same basic sized description).

Different weapons for different missions.

 

[racevedo88]

Thats if the forward observer is down around one meter altitude. At between two and three meters above a lake surface I've measured the horizon at 13.4 km distance (8.3 miles). With a hill I could observe fires out past 15 km range in the Mojave desert. Tho spotting the burst with standard binoculars that far is difficult. Battle ships in WWII were observing the enemy, getting accurate range fixes, and occasionally hits out past 25km. The record ship to ship hit was IIRC at 28,000 yards. Need to check that.

Let’s not forget there were also using balloon observers at the time.