caliber size
- Thread starter zoolander
- Start date
It depends. Bigger is better in some respects; for example, a 152mm cannon (which has not been installed in BE prototypes, btw, just 125mm) could fire a big anti-tank missile that could do a good job of defeating compound armor types at long range. On the other hand, when you get shells that big, your ammo storage is seriously limited, both by the size of the rounds and by the size of the autoloader equipment (human loader is out of the question). NATO tanks have standardized on 120mm, although both M1 and Leo2 can accept the Rheinmetall 140mm cannon. Current thinking appears to be that the new generation of APFSDS can deal with the current threat, so there's no need to upgrade to the 140mm yet. I'm not sure what the latest reactive armor (Kontakt-5, Kaktus) will do to a 120mm APFSDS; the ERA developers are obviously confident that their flyer plates will be able to break or deflect them.
The other thing to deal with in a big caliber like 152mm is recoil. It's significantly more than 125mm, so the recoil-mitigation system is going to have to be bigger and heavier, and you might have to beef up the suspension, too. So for all the weight and size penalties, 152mm may not be worth it yet, especially when the current generation of 125mm guns (and 120mm in the West) is plenty powerful for what they need to do. We'll see what T-95 has on it, but my money's on 125mm.
The other thing to deal with in a big caliber like 152mm is recoil. It's significantly more than 125mm, so the recoil-mitigation system is going to have to be bigger and heavier, and you might have to beef up the suspension, too. So for all the weight and size penalties, 152mm may not be worth it yet, especially when the current generation of 125mm guns (and 120mm in the West) is plenty powerful for what they need to do. We'll see what T-95 has on it, but my money's on 125mm.
A
Aussie Digger
Guest
It's not the size that counts, it's what you do with it that's important... :haha
Seriously though, smaller calibre ammunition, is normally cheaper, and has a higher velocity. Larger calibre amo generally has greater lethality. It's a case of "horses for courses" really.
As to the 152mm tank gun/missile combo. It's been tried before, (on the Sherridan most notably) it was not a great success. The tremendous pressures involved in tank gun firing does not do much for the delicate electronics of guided weapons. I know guided weapons are successfully integrated on Artillery pieces, so I can't explain technically why this is so, but it has been shown to be the case...
Seriously though, smaller calibre ammunition, is normally cheaper, and has a higher velocity. Larger calibre amo generally has greater lethality. It's a case of "horses for courses" really.
As to the 152mm tank gun/missile combo. It's been tried before, (on the Sherridan most notably) it was not a great success. The tremendous pressures involved in tank gun firing does not do much for the delicate electronics of guided weapons. I know guided weapons are successfully integrated on Artillery pieces, so I can't explain technically why this is so, but it has been shown to be the case...
Beside the actual size of the gun system, the type of ammunition is also a key part of the system. The type of HE, HEAT, Kinetic Penetrators used all have different effects. Many militarises use Tungsten kinetic penetrators, while the U.S. is still using depleted uranium (DU). These heavily metals allow for the best armor penetration in combat.
Safe? Not at all! They'll go through anything, as many an Iraqi tanker can attest. Or did you mean for the Abrams crew? 
There doesn't seem to be any definitive study that says DU rounds are significantly more toxic than the other hazardous materials tankers work around all the time. At least, there aren't any reliable reports that say so in the public arena that I've seen. Take that for what it's worth, I suppose. All in all, I'd say an American tanker is more likely to die from something other than exposure to DU rounds.
There doesn't seem to be any definitive study that says DU rounds are significantly more toxic than the other hazardous materials tankers work around all the time. At least, there aren't any reliable reports that say so in the public arena that I've seen. Take that for what it's worth, I suppose. All in all, I'd say an American tanker is more likely to die from something other than exposure to DU rounds.Of course there are two sides to this coin. The tank crew using the rounds may be safe because basically they handle the round the way they are supposed to. However when the round is used and the DU is spread around the landscape, getting into toxic contact with it (eg via breathing) should become more likely.
But thats just an uneducated guess by me.
BTW @zoolander: The NATO standard is 120 mm nowadays. The Russians, Chinese etc are using 125 mm.
Germany and Switzerland experimented with 140 mm tank guns but the gains were deemed insignificant in comparison to the added weight, reduced ammo storage and a whole bunch of technical issues resulting from fitting the gun on existing MBT, being the Leo 2 in both cases. Compatibility with other NATO members, esp. the US was a point in the decision against such a move as well, since the US were not interested in the 140 mm-step and are planning to introduce their own new gun (XM291) at some point in the 201X timeframe.
So the alternative is increasing barrel length which is exactly what one can see with the Leopard 2A6.
But thats just an uneducated guess by me.
BTW @zoolander: The NATO standard is 120 mm nowadays. The Russians, Chinese etc are using 125 mm.
Germany and Switzerland experimented with 140 mm tank guns but the gains were deemed insignificant in comparison to the added weight, reduced ammo storage and a whole bunch of technical issues resulting from fitting the gun on existing MBT, being the Leo 2 in both cases. Compatibility with other NATO members, esp. the US was a point in the decision against such a move as well, since the US were not interested in the 140 mm-step and are planning to introduce their own new gun (XM291) at some point in the 201X timeframe.
So the alternative is increasing barrel length which is exactly what one can see with the Leopard 2A6.
There's a good example: German PzH2000 with a 155mm L/52 big gun, usually it is used as a howitzer, but with some smart ammo or big anti-tank missille, it has the capability to kill a MBT at the range of 20Km...that's horrible, none of the current MBTs can resist an 155mm ammo's attack(even ordinary ammo), it will be smashed to pieces...With certain ammo, 155 gun can be a AA gun with lower rate but higher quality to destroy certain targets. I have seen a pic about PZH 2000, the German remove the army gun onto a big ship for some tests, maybe for testing of the capablibity attacking the coast targets and ships...Smart German...
They become a issue after they hit a target, a DU penetrator even looks different when it hits a target vs titanium and tungsten penetrators. It was what we called a dirty target for destroyed vehicles, any thing with in a 300 meters 360 degree radius you needed to stay out of that area. Ever wonder what Gulf war syndrome sickness comes from?Safe? Not at all! They'll go through anything, as many an Iraqi tanker can attest. Or did you mean for the Abrams crew?
Eckerl is very correct. DU rounds work great at killing MBT's but they make the whole area contaminated. A lot of ally soldiers were exposed to powderized DU during the war, and it is a leading theory on what causes some of the cases of Gulf War Syndrome. DU dangers are the reason why many nations use Tungsten in their rounds. Why do think the Leo's got a new gun? Because the German Army wanted a cannon that can penetrate like DU but using a Tungsten round. The longer caliber allows the new cannon to do so.
Post-hit toxicity may very well be an issue for troops and others working around the destroyed vehicle. The original fear in the media, AIUI, was that the DU rounds were toxic to anyone simply handling the intact rounds, e.g. the turret crew as the loader loads the DU round. That, from what I understand, is not a significant issue.
Grand Danois
Entertainer
The Swedes made a survey on their soldiers in Kosovo.
The issue was if the DU shells from the Avenger gun on the A-10 fired during the Kosovo Air War posed a health risk.
They found out that the background radiation at home in Sweden was more significant (they have lots of igneous rock) than in the areas the DU shells were fired. I don't how much they looked at ingestion.
As I understand it, the reason for using DU is because it is cheap and available in quantity. They do not necessarily perform better than eg tungsten penetrators.
The issue was if the DU shells from the Avenger gun on the A-10 fired during the Kosovo Air War posed a health risk.
They found out that the background radiation at home in Sweden was more significant (they have lots of igneous rock) than in the areas the DU shells were fired. I don't how much they looked at ingestion.
As I understand it, the reason for using DU is because it is cheap and available in quantity. They do not necessarily perform better than eg tungsten penetrators.
You are correct on the availability of DU, but also DU has a better density level than tungsten, we even placed it as a armor package on the M1A1 heavies. I know that for the 25mm Bushmaster that we went to a DU penetrator, but I did not know that they switched from titanium to dU on the 40mm carried on the A-10.
Grand Danois
Entertainer
There is also the matter of toughness in this equation (I guess).
I thought the 30mm GAU-8 Avenger had used DU as its primary ammo all along. But not in Afghanistan.
Sorry - I meant 30mm, I do not see the reasoning into having to go to DU because of the fact that the A-10 attacks the top and rear of armored vehicles, the weakest area`s when it comes to armor protection. Oh well leave it to us for overkill.There is also the matter of toughness in this equation (I guess).
I thought the 30mm GAU-8 Avenger had used DU as its primary ammo all along. But not in Afghanistan.
Grand Danois
Entertainer
I don't have issues with DU. But if there are other materials that gets the job done, then ditch the controversial ones, like DU.
Agreed - Back in the late 80`s there was a study conducted by some folks in the U.S that estimated that if a war had broken out between NATO and Warsaw Pact forces that it would take 10 - 15 years just to get the soil conditions back to normal from being contaminated from all the DU munitions that would of been exchanged.
I think DU has better overall penetrating performance than tungsten (I've not heard of titanium being used in KE penetrators, btw; although strong, it's not dense) due to its superiority in the areas of density, ductility, and behind-armor effects. The first two are, IIRC, marginal improvements, but DU's pyrophoric qualities mean worse things happen inside the vehicle after penetration. I'm guessing that's one of the main reasons the US DoD likes DU over tungsten.
The U.S designation for the 105mm Titanium tipped round was M774, the Russians also have gone to DU KE rounds also, matter of fact they have had them
for quite some time now, giving the 125mm a major boost in punching power. A soviet BR-11 will punch a hole in the frontal armor of a M1A1 at 1600 m. Germany has gone back to a Tunsten KE penetrator, but they extended the gun tube on the LEO 2 A6, they are also testing the L-44 140mm as a possible replacement.