Tiger accuracy

[rexford]

The data that we obtained on German ammo scatter showed the Tiger with smaller dispersion than the Panther round. The data was from a WW II German source, and consisted of trajectory sheets with all sorts of information.

Like anything else, there are often multiple sets of the same sort of data, perhaps with different dates, that show revisions and changes. Tests are rerun, different lots of ammo are used, etc.

It is quite possible that there are two different sets of data for 88L56 and 75L70 scatter that show opposite comparative results. The results that Mr. Tittles compares are close enough that a small change could reverse the "winner".

[Mr. Tittles]

I would agree that they are closely matched.

I read an account of a Panther in British service during the war. It could loft HE rounds into windows at considerable distances. Ive also read that the French testing of the Panther showed remarkable accuracy even using HE to hit tanks at distance.

But these are stationary targets. Hitting moving targets would be harder. A nice way to hit moving targets is to have a fast moving shell. The physics behind this being that a reduced time of flight means less lead and possible error. The flatter trajectory doesnt hurt either.

I think when the 88L56 Tiger gun was first around, it so outclassed other MBT guns that it built a certain lore of 'supergun' status. Its velocity, heavy shell, optics, elite crewmen, etc, etc all built the weapons reputation. being behind thick armor diddnt hurt either.

[Mr. Tittles]

I think a good topic is who had the easiest time estimating/measuring range? Its pretty clear that initial range estimation gets to be a critical factor as a function of distance.

Something that would make guessing range easier is if the enemy had vehicles that were all the same size. The russian T34 would be a very common vehicle and the germans could train their gunners very effectively by using this vehicle type. Conversely, the russians had a slew of MBTs, AG, SPAT, etc that they were shooting at. For them to judge distance on vehicle size is much more difficult.

The German sights included a method of judging range for the gunner after he was assigned a target, heading, initial range by the commander.

Another critical factor is followup shots. The critical thing being the observation of the tracer. In the case of the US, there is test data that claims that observation by the gunner is seriosly hampered by the smoke from the gun itself. This being on a windless day without dusty ground conditions.

[Redwolf]

Originally posted by Mr. Tittles:

But these are stationary targets. Hitting moving targets would be harder. A nice way to hit moving targets is to have a fast moving shell. The physics behind this being that a reduced time of flight means less lead and possible error. The flatter trajectory doesnt hurt either.

I know I should know better and keep out of this, but it is sad to see that you collect so excellent data on so many factors and then fail so blatantly to apply them and rate them against each other.

If you don't have Rexford's book, he has an excellent introdution to a hit probability model.

I don't know how sophisticated your math is but if you do a quick calculation about how much of a range error leads to what kind of miss probability for what guns it would help you a lot. Rexford's book has one.

[John Kettler]

rexford and troops,

I believe I may have a possible explanation for the reported lesser dispersion of the 88 L/56 vs. the 88 L/71--barrel whip. When I was at Hughes, my department manager and our Weapon Analyst, a buddy of his, were battleship grogs, each owning hundreds of juicy historical and technical volumes. One, BRITISH BATTLESHIPS(?), talked about a problem noted during firing trials for the 14"(?) gun. The problem was excessive dispersion, traced to barrel whip caused by heavy powder charges. Reducing the charge a bit dropped the MV a few hundred feet per second, and though annoying to the Royal Navy which wanted maximum penetration, eliminated the problem altogether, and the gun was accepted for service, where it went on to do yeoman work.

Seems perfectly reasonable to me that the shorter barreled 88 would have less whip than the long 88, thus less dispersion. Also, I believe the driving factor behind the 88 L/71 was the need for greater penetration against more thickly armored targets, rather than merely extending the engagement range.

Regards,

John Kettler

[Mr. Tittles]

Redwolf are you really sad? Thats too bad.

Anyway..

I believe whip could be related to rifling twist rates. In ball screw devices (which are similar to the rifling issue), there is a maximum speed that you can run them out before they start whipping. A ball screw device is fixed at both ends and the rapid ball nut movement cause a 'jump-rope' effect to take place. This aggravates the motion and the device will vibrate badly and stall out. The longer the ballscrew, the more pronounced this effect is.

In a gun system, it is fixed on one end and open on the other (the barrel end). The effect would be not a 'jump rope' but rather a jerk on the barrel end as the aggresive twist bites into the rapidly accelerating shell.

On a short barreled weapon, like the 75mmL24, this effect would be small or negligible. As the barrel gets longer and the powder charge larger, it would be more pronounced. Another factor would be barrel thickness. A thicker tube would be more resistant to this phenomena.

It would be interesting to see twist rates on these high velocity weapons. Perhaps variable twist rates were also used?

[ February 15, 2004, 12:24 PM: Message edited by: Mr. Tittles ]

[Jonny]

I definately agree with the accuracy issue of the Tiger I.

For those of you who haven't ever used a simulation of firing a shell, like that of an AT gun or similar, you can immediately tell the difference between a higher velocity shell than a slower velocity shell... good example - Pz IV /w 7.5cm L/24 vs Pz IV /w 7.5cm L/48. There is simply no comparison between how much easier it is to send a shell which is nearly guaranteed to be heading straight lined on towards your reticle.

Higher velocity shells simply don't fall off as fast in near ranges, and hits are incredibly easy to achieve. Its simple point and click.

Not only that, it makes perfect sense if you think about it.

However, in CMAK, I actually see better accuracy in the Sherman than in the Tiger at times... I have noticed a few good times a Regular Sherman crew picking off PzIVs and PzIIIs in 1 shot kills (I'm talking Shermans which are not moving). I haven't done any testing, but I am certain that this phenominom is some sort of balance issue...

Oh well.

JW

[Mr. Tittles]

This line up shows a Panther AP round third from the right. The shell to the right of it is a 88mm HE. The Shell on the far right is a 88mm L71 HE. The shells to the left of the Panther AP are 75mm HE L48 and L24.

[Mr. Tittles]

Originally posted by Jonny:

I definately agree with the accuracy issue of the Tiger I.

For those of you who haven't ever used a simulation of firing a shell, like that of an AT gun or similar, you can immediately tell the difference between a higher velocity shell than a slower velocity shell... good example - Pz IV /w 7.5cm L/24 vs Pz IV /w 7.5cm L/48. There is simply no comparison between how much easier it is to send a shell which is nearly guaranteed to be heading straight lined on towards your reticle.

Higher velocity shells simply don't fall off as fast in near ranges, and hits are incredibly easy to achieve. Its simple point and click.

Not only that, it makes perfect sense if you think about it.

Oh well.

JW

Earlier a tanker with actual experience with Sherman 76mm said as much.

[gibsonm]

Originally posted by Mr. Tittles:

This line up shows a Panther AP round third from the right. The shell to the right of it is a 88mm HE. The Shell on the far right is a 88mm L71 HE.

Black for HE?

[Mr. Tittles]

The Panther AP round is the only black 75mm-88mm projectile in the pics (note:its not HE). The other 75mm-88mm rounds are HE. Dead giveaway is the silver colored fuse (which could be seen easily in the dark). Later black AP rounds had white painted noses to assist in loading in dark environments.

So we have R to L, Tiger II HE, 88L56 HE, Panther AP, 75mmL48/L43 HE, 75mmL24 HE. And then some others of smaller caliper appear to be a 50mmL60 HE, 50mm L42 APCR and a 37mm AP. (Oh! I hope that wasn't so confusing/unclear that it brings a SimonFox diatribe)

The 75mmL24 and 75mmL48 and 88mmL71 HE rounds are really a greenish color. According to the Panzer IV universe website, this is olive green. HEAT rounds for the weapon also had olive coloring as well as smoke rounds.

http://ourworld.compuserve.com/homepages/willphelps/Specs-03.htm

The 88mm HE rounds for FlaK guns appear yellow in photographic evidence.

Band colors on german rounds denote tracer color I believe.

[ February 16, 2004, 04:22 PM: Message edited by: Mr. Tittles ]

[Mr. Tittles]

Looking down a Tiger I barrel

[Mr. Tittles]

There is a side by side of Panther HE and AP on this website, Left and Right. The Panther HE also appears to follow the olive green coloring scheme. The FES on the HE shell refers to the driving band material (I think).

An interesting side note (oh no! Mr.Fox must suffer additional information in the same thread, boohoo) is that the Panther round initially had one driving band and then later two. web page

[ February 15, 2004, 08:34 PM: Message edited by: Mr. Tittles ]

[Soddball]

Originally posted by Mr. Tittles:

Looking down a Tiger I barrel

I have a better photo than that from Bovington.

[Noba]

Originally posted by Soddball:

</font><blockquote>quote:</font><hr />Originally posted by Mr. Tittles:

Looking down a Tiger I barrel

I have a better photo than that from Bovington. </font>

[Mad Russian]

Just a thought but does CM take into account crew experience on the ability to hit a target?

It seems to me that the basic premise for this whole string of posts is can a Tiger I hit a tank at whatever range with a high degree of accuracy. The answer of course is yes.

Lay the gun.

Set the sights.

Hit the target.

IF the gun and target DO NOT MOVE you will hit it every time. So the variable is not can the Tiger hit the target with a high degree of accuracy because we know the system can do that. The question is whether the CREW can hit the target with a high degree of accuracy.

This then brings into play all the things that Rune, Jason and others have been pointing out. The variables that interact with the human gunner and his ability to react and adjust his fire to meet those variables correctly enough to get a hit.

Just MHO.

Panther Commander

[ February 16, 2004, 02:51 PM: Message edited by: Panther Commander ]