Jump to content


Tank gun calibers, a question


This topic has been archived. This means that you cannot reply to this topic.
25 replies to this topic

Gabo #1 Posted Jul 08 2012 - 23:39

    Staff sergeant

  • Beta Testers
  • 12921 battles
  • 265
  • [FGTVE] FGTVE
  • Member since:
    09-30-2010
Do you guys know what factor came into play when deciding the diameter of the guns?,
For example, why did the germans use a 88mm gun and not a 89 or 90?
why are the russian guns 152 and not 150 or 155?
And as a bonus question, why are the rifle bullets 5.56 and 7.62 and not just plain 5, 6 7 or 8?

And how is the lenght of the barrel decided?, did they build an 88/69, an 88/70, an 88/71 etc and decided which was the best regarding accuracy and weight or it was something else?

Thanks a lot for any replies

Slakrrrrrr #2 Posted Jul 08 2012 - 23:51

    Major

  • Players
  • 16982 battles
  • 5,591
  • [3BAT] 3BAT
  • Member since:
    07-16-2011
Shells/Bullets are often measured in imperial measurements. 152mm = 6 inches and 7.62mm = .30 cal or .3 inches in diameter.

iHuntTanks #3 Posted Jul 08 2012 - 23:53

    First lieutenant

  • Beta Testers
  • 23334 battles
  • 935
  • Member since:
    01-21-2011
In my opinion (I'm not an expert, just my personal opinion), is that these 152mm guns didn't exists in the first place for most of them (most of them were never mass-produced except for the KV-2 152mm howitzer, and it was used to blow apart fortifications as far as my wikipedia earned knowledge goes).

Why the germans used an 88 gun? Probably because the smaller caliber = faster shot = less propellant needed. The shot, by being of a smallish caliber, is large enough to do damage to a M4, but small enough to be easily enough producable. The small caliber allows (personal thinking, might be wrong) more pressure to be used on the shell to propell it (For example, let's say 100 grams of a propellant can propell a 100mm shell 100m. But if you were to use a 88mm gun, then there is less weight/explosive to propell, therefore leading to a faster and hopefully lighter shell). The Length helps accuracy (You hopefully know about how long the barrett sniper rifles in CoD or whatever are, and that long barrel is to help the accuracy of the high powered shot, as a short barrel wouldn't be able to keep the high-powered shot in line.).

In terms of why the caliber stayed/stays the same for them, it's easier to simply choose "Alright, use the 88mm measurement for all our guns!" than saying "We should have many different calibers!". It's standardisation in how all of the manufacturing factories that were already producing 88 guns/shells don't need to change anything, and the new factories just get given the order to "make 88 guns/shells".

Rifle bullets are different. Someone made a post about it, but a 5.5mm bullet has, as you might know from the logic of this post, less penetration. This is bad when you are shooting at say, a tank or whatever, but when shooting at and hitting a human, the 5.5mm bullet is actually better than a 7.62 bullet because the 7.62 gets inefficient overpenetration. That means the 7.62 is wasting some propellant (the bullets are going THROUGH the target).

Hope this helped! :D

iHuntTanks #4 Posted Jul 08 2012 - 23:54

    First lieutenant

  • Beta Testers
  • 23334 battles
  • 935
  • Member since:
    01-21-2011

View PostSlakrrrrrr, on Jul 08 2012 - 23:51, said:

Shells/Bullets are often measured in imperial measurements. 152mm = 6 inches and 7.62mm = .30 cal or .3 inches in diameter.

Oh, thank you for telling me something I hadn't heard before! Never knew that personally tbh :\ Interesting fact...

Slakrrrrrr #5 Posted Jul 08 2012 - 23:55

    Major

  • Players
  • 16982 battles
  • 5,591
  • [3BAT] 3BAT
  • Member since:
    07-16-2011
I love double posts...

Edited by Slakrrrrrr, Jul 08 2012 - 23:55.


Akuzimo #6 Posted Jul 09 2012 - 00:13

    Sergeant

  • Players
  • 2671 battles
  • 246
  • [VPG-R] VPG-R
  • Member since:
    03-27-2011
Now what decides the length of the barrel is the particular role of the tank.  If it's something like a StuG III (SturmGeschutz or Assault Gun), it might typically be found with a much shorter barrel on its cannon, because its goal is to be an assault gun, or more or less a shotgun on tracks.  They even equipped one of these things with a rocket launcher that practically had to be point blank, but it blew bunkers to pieces.

If you're in something like a Tiger, which is meant to handle enemy tanks from a great distance, they will choose a much longer barrel as it not only increases the force of which the round exits the barrel due to its length, it makes the shot much more accurate.  Also, some factors like cost and time of production also could have played roles in some tanks getting unorthodox sizes of barrels and armament.

-Akuzimo

blazerx00x #7 Posted Jul 09 2012 - 00:22

    Corporal

  • Beta Testers
  • 8446 battles
  • 19
  • [PRO_S] PRO_S
  • Member since:
    10-03-2010
In some cases the rounds are designed first according to a mission in mind (i.e. Anti-Tank). The round has to penetrate a certain thickness of armor, has to fly a certain distance while maintaining a certain amount of accuracy and so on. In the end iHunt is correct and that a certain amount of standardization is introduced and the logistics of a single caliber round is introduced.

According to an article I read once as to why the 88's were still produced late in the war was as much a psychological as it was practical. You could just mention that there were 88's nearby and some tank crews were instantly at a disadvantage weather the round could pen their armor or not.

Gabo #8 Posted Jul 09 2012 - 00:32

    Staff sergeant

  • Beta Testers
  • 12921 battles
  • 265
  • [FGTVE] FGTVE
  • Member since:
    09-30-2010
my question is if anyone knows exactly why those specific measures, i know the whole small caliber, high velocity thingy, i just wanted to know if there are stories as to the exact use of calibers (i mean, for all we know they could have used a 87cm gun, but no, they used the 88, why?)

_RayS_ #9 Posted Jul 09 2012 - 04:58

    Sergeant

  • Players
  • 7092 battles
  • 231
  • [FRU] FRU
  • Member since:
    09-25-2011
They used the 88 becuase Hitler wanted a heavy tank with the 88. It was a AA cannon before its new tank- busting role.

As for the Soviet 76.2mm, I think the specific measure was used to simplify ammo logistics. The Red Army also used 76.2mm antitank guns, and I am guessing that the rounds could be shared between guns and tank guns. Correct me if I am wrong.

Also, longer barrel = more muzzle velocity = more pen = more accurate.

Zinegata #10 Posted Jul 09 2012 - 06:37

    Major

  • Beta Testers
  • 7438 battles
  • 4,760
  • Member since:
    07-27-2010
The Soviets had an excellent 76.2mm gun that served in the anti-tank and artillery role, so standardization may have been a factor.

thundersaver #11 Posted Jul 11 2012 - 11:30

    Major

  • Players
  • 3647 battles
  • 2,904
  • Member since:
    08-01-2011

View PostGabo, on Jul 08 2012 - 23:39, said:

Do you guys know what factor came into play when deciding the diameter of the guns?,
For example, why did the germans use a 88mm gun and not a 89 or 90?
why are the russian guns 152 and not 150 or 155?
And as a bonus question, why are the rifle bullets 5.56 and 7.62 and not just plain 5, 6 7 or 8?

And how is the lenght of the barrel decided?, did they build an 88/69, an 88/70, an 88/71 etc and decided which was the best regarding accuracy and weight or it was something else?

Thanks a lot for any replies

Longer barrels in general lead to a much more accurate gun, but that does not mean it has more muzzle velocity or stopping power as a matter of fact. Longer barrels require rounds/shells/bullets with a longer casing to allow for better muzzle velocity. Had the a round from a shorter barrel been used to fire in the long barrel the round would not even travel as far as it would with a shorter barrel.

The main point of a longer barrel is to channel the muzzle energy to a more concentrated source, or the center allowing for a much more accurate weapon overall. However shorter barrel weapons tend to have more stopping power than longer barrels in convention because less energy released during the ignition of the shell is lost to the surrounding compared to one with a longer barrel.

This is quite evident that tanks of world war 2 that used heavy caliber guns mostly used short barrel lengths because the energy lost is somewhat less and since heavier shells(above 125mm) would require a two-piece ammunition to be a successful high-velocity anti tank gun, the shorter barrel allowed for less explosive powder needed for the propelling of the round, thus enabling larger rounds to leave the barrel more quickly but without the accuracy.

So the decision for longer barrels comes into effect of what the intended combat purpose of the tank. Was the tank meant to blow up fortifications and support infantry? if so it would come with a short barrel, with a reasonable shell size, usually 75mm and above and its main shells would be HE for the purpose of killing infantry and destroying fortification.

How about tank engagement? They would than come with longer barrels with heavier shells with longer shell casings. This is to allow the successful engagement of tanks over longer distances which would prove fatal against infantry support tanks which lack the capable means of fighting at such ranges. As your fighting against tanks , the cannon caliber used would usually be quite high to allow for massive amounts of kinetic energy to be in stored in the shell upon contact, helping penetrate tank armor.

On with the calibre of my the 152, not the 155 or 150, or the 88 and why not the 89 or 90mm, is similar to what SlaKrrr said that measurements were in imperial measurements or inches. However if you went to look up the 88 to the 90mm you would get sizes like 3.465, 3.5 inches and what not which are not really "nice numbers". The reason to this was beyond my explanation and i tried to do a bit of simple research, and well mostly what i came up with, the 88mm was successful adopted not because of its caliber, but because one of the Nazi generals fired it at tanks.

The gun was previously common in the arsenal of AA on the Nazi battleships, and thus it was later used on land. However its name came from the use as an anti tank weapon which came as a coincidence. I did a bit more reading about the why the US never tried to add the 88 into their arsenal and i found this: http://answers.yahoo...11131736AAdMg2s

It is an interesting read, but to sum it up, it just said that the gun caliber really meant no difference, the only reason why the the 88 was so famous was also because it was used effectively by the Germans which granted its notoriety in the war, but other than that is was a very in-capable gun till it was made into an anti-tank gun as seen here as well:  http://answers.yahoo...10074555AAYPgoQ

Edited by thundersaver, Jul 11 2012 - 11:32.


blurr91 #12 Posted Jul 11 2012 - 20:00

    Major

  • Players
  • 12321 battles
  • 2,396
  • Member since:
    05-21-2011
Sometimes it's just a convention.  Somewhere along the line, a caliber was adopted, and it became the standard of that nation.  It's expensive to change calibers because the machining tools were set for that caliber.

Soviet 152mm were really 6" guns.

US 6" guns were 155mm.

Germans went with metric early and had 150mm guns.

German AA guns were 88mm.

American AA guns were 90mm.

Sherman's 75mm gun was modified from the famous French 75.

Sherman Firefly's 3" gun was really the 17 pdr.

The more you look into these, the more confused you'd get.  Militaries are very conservative organizations.  They don't like to change things.  Even when they do, they keep old things around to further confuse you. :Smile_Default:

roadtoinfinity #13 Posted Jul 27 2012 - 13:05

    Staff sergeant

  • Players
  • 5535 battles
  • 251
  • Member since:
    03-09-2011

View PostZinegata, on Jul 09 2012 - 06:37, said:

The Soviets had an excellent 76.2mm gun that served in the anti-tank and artillery role, so standardization may have been a factor.

They didn't have 76.2 MM gun, it was a rifle round not a tank cannon round. Anyways the 7.62 was a NATO round used by the US and UN

blurr91 #14 Posted Jul 27 2012 - 20:47

    Major

  • Players
  • 12321 battles
  • 2,396
  • Member since:
    05-21-2011

View Postroadtoinfinity, on Jul 27 2012 - 13:05, said:

They didn't have 76.2 MM gun, it was a rifle round not a tank cannon round. Anyways the 7.62 was a NATO round used by the US and UN

No, the Soviets, and numerous other nations had employed 76.2mm guns, which just happened to be 3".

You're confusing the 76.2mm gun on the Marder II (captured Soviet artillery http://en.wikipedia....gun_M1936_(F-22)) with the standardized 308 Winchester (7.62x51mm) used by NATO during the Cold War in their battle rifles.

There are literally hundreds of 3" guns (76mm class) used over the last century.  Just type in "76mm" in Wikipedia and you'll see.

thejoker91 #15 Posted Jul 27 2012 - 21:03

    Major

  • Beta Testers
  • 13820 battles
  • 5,571
  • [RELIC] RELIC
  • Member since:
    09-23-2010

View Postroadtoinfinity, on Jul 27 2012 - 13:05, said:

They didn't have 76.2 MM gun, it was a rifle round not a tank cannon round. Anyways the 7.62 was a NATO round used by the US and UN

76,2 =/= 7,62

just sayin.

roadtoinfinity #16 Posted Jul 28 2012 - 17:53

    Staff sergeant

  • Players
  • 5535 battles
  • 251
  • Member since:
    03-09-2011

View Postblurr91, on Jul 27 2012 - 20:47, said:

No, the Soviets, and numerous other nations had employed 76.2mm guns, which just happened to be 3". You're confusing the 76.2mm gun on the Marder II (captured Soviet artillery http://en.wikipedia....gun_M1936_(F-22)) with the standardized 308 Winchester (7.62x51mm) used by NATO during the Cold War in their battle rifles. There are literally hundreds of 3" guns (76mm class) used over the last century. Just type in "76mm" in Wikipedia and you'll see.

View Postthejoker91, on Jul 27 2012 - 21:03, said:

76,2 =/= 7,62 just sayin.

Oh i thought they were talking about NATO rounds as the only 7.62 rounds i know of, never heard of 76.2 mm or 3 in gun's before

bullofscapa #17 Posted Aug 22 2012 - 04:14

    First lieutenant

  • Players
  • 4454 battles
  • 602
  • Member since:
    04-26-2011

View Postblurr91, on Jul 11 2012 - 20:00, said:

Sometimes it's just a convention.  Somewhere along the line, a caliber was adopted, and it became the standard of that nation.  It's expensive to change calibers because the machining tools were set for that caliber.

Soviet 152mm were really 6" guns.

US 6" guns were 155mm.

Germans went with metric early and had 150mm guns.

German AA guns were 88mm.

American AA guns were 90mm.

Sherman's 75mm gun was modified from the famous French 75.

Sherman Firefly's 3" gun was really the 17 pdr.

The more you look into these, the more confused you'd get.  Militaries are very conservative organizations.  They don't like to change things.  Even when they do, they keep old things around to further confuse you. :Smile_Default:

Dont forget about the 128mm the Germans used for heavy AA weapons. :Smile_glasses:

The Germans also used an 88mm on the Type VII and a 105mm on the type IX uboats.

I think, like other's have said, I think it depends on the nation. Germany used the 75, 88, and 128mm rounds. Russia, 76.2, 85, 100, 122 and 152mm ( might have missed a few in there), U.S. liked the 75, 76 and 90mm cannons.

blurr91 #18 Posted Aug 22 2012 - 18:59

    Major

  • Players
  • 12321 battles
  • 2,396
  • Member since:
    05-21-2011

View Postbullofscapa, on Aug 22 2012 - 04:14, said:

Dont forget about the 128mm the Germans used for heavy AA weapons. :Smile_glasses:

The Germans also used an 88mm on the Type VII and a 105mm on the type IX uboats.

I think, like other's have said, I think it depends on the nation. Germany used the 75, 88, and 128mm rounds. Russia, 76.2, 85, 100, 122 and 152mm ( might have missed a few in there), U.S. liked the 75, 76 and 90mm cannons.

Our heavy AA gun was the 5" dual purpose, which just happened to be 127mm.  I don't think we ever tried to put that thing on a tank though.

Our tank guns went from 75mm, to 76mm, to 90mm, to 105mm, to 120mm, and a different 120mm gun today.

Our naval guns in WW2 were 3", 5", 6", 8", 12" (Alaska class), 14" (old battlewagons), 16" (old battlewagons and new fast battleships).

By the way, I just watched the movie Battleship.  It was horrible.  It would be OK if you have a bunch of friends getting drunk with you and watching it for free on Netflix or something.  Make sure there's plenty of smart ass comments to keep the movie entertaining. :Smile_veryhappy:

Gabo #19 Posted Aug 22 2012 - 19:35

    Staff sergeant

  • Beta Testers
  • 12921 battles
  • 265
  • [FGTVE] FGTVE
  • Member since:
    09-30-2010
tnx a lot for all the replies guys, now for more, did most of the guns derive from ww1 arty calibers and those from sail age ships?, whats the genealogy tree of this guns?

blurr91 #20 Posted Aug 22 2012 - 23:04

    Major

  • Players
  • 12321 battles
  • 2,396
  • Member since:
    05-21-2011

View PostGabo, on Aug 22 2012 - 19:35, said:

tnx a lot for all the replies guys, now for more, did most of the guns derive from ww1 arty calibers and those from sail age ships?, whats the genealogy tree of this guns?

Yes and no.

Yes, most guns from WW2 were derived from WW1 designs as there was only a 20 year gap between them.  Tank wise, the Sherman's 75 was derived from the famous French 75.  The Sherman 105 was a modified 105 field artillery, which came from WW1.  37mm and 57mm anti-tank guns were developed either late in the war or during the interwar years.  They were quickly obsoleted by thicker armor early in WW2.

Ship wise, I believe only the 5", 6" and 8" guns were retained from WW1.  Dreadnoughts mostly used 12" and 14" guns in WW1.  Those were superceded by 16" guns late in WW1 and the interwar years.  Of course even though they had the same caliber, the guns themselves and the projectile might be (in most cases) different.

These are only for US guns.  I don't know much about other nations and their history.  I know Brits used 15" guns extensively and Germans had 11" guns.

I don't know about the lineage of breech loading guns to earlier muzzle loaders.  I'd imagine they are not related at all.  Muzzle loaders usually used blackpowder for propellent.  Breech loaders, by the time they were practical, had cordite and smokeless.  Those propellent were way more powerful than blackpowder and the guns built to contain that pressure were very different.

Here's an interesting site I've found a while back:

http://navweaps.com/...s/WNUS_Main.htm