First test with Fireflies vs King Tiger

[Vanir Ausf B]

Someone posted a link to a 5 part youtube series examining who killed Wittmann (sp?). Part of that showed the location of a Firefly, ~800m, firing at Tigers from the Tigers' 2 o'clock. 3 shots, 3 hits. The Tigers were advancing.

That's a real world result, backed up with some impressive post-battlefield examinations.

No comment on the KT accuracy (or frequency of being put hors de combat), purely a commentary on the Firefly accuracy. First round hits at 1,000m should not be a rarity. It seems they are not.

Depends on the ammunition being fired. APCBC should indeed be very accurate. APDS ,on the other hand, should be lucky to hit the broad side of a barn at 1000m.

[dieseltaylor]

With very high velocity tank guns you could range them to say 1200 metres and they would hit anything under say 8ft that was in the way. And that is because the shells would be travelling very flat.

As an aside the Tiger 1 would fire HE at far distant targets as it was more accurate than the AP shell.

[hoolaman]

Depends on the ammunition being fired. APCBC should indeed be very accurate. APDS ,on the other hand, should be lucky to hit the broad side of a barn at 1000m.

Someone posted a while back some WWII era test-range data where a smaller calibre (57mm?) APDS test failed to hit the target. At all. On a test range! It was theorised that the ammo was a bad batch.

There is definitely enough evidence to support a reasonable failure rate with APDS, but my understanding is that a bad shell would be a spectacular failure like a dud ATGM curling away, but a good shell should be dead straght.

What proportion of duds vs winners? I don't know where to start with that one.

[slysniper]

Depends on the ammunition being fired. APCBC should indeed be very accurate. APDS ,on the other hand, should be lucky to hit the broad side of a barn at 1000m.

I dont think you will like the answer, but another test to focus on that will likely prove your special ammo was the ammo doing the penetrations.

But I did not verify that, it requires you to sit and watch the tank firing and check which ammo was used at the time of penetration. I do know they did fire APDS, since the counts changed, but did not verify they were the kills.

Now when I ran the 500m test, I did see that it was the APDS in general, so I have a hard time beleiving the normal ammo managed the kills at 1000m when it was not doing much at 500m

So your concerns are likely justified, but I will let you prove that issue, but you likely have one.

[Vanir Ausf B]

What proportion of duds vs winners? I don't know where to start with that one.

From UK Warrant Office Reports WO 291/1263 and WO 165/135, 22 Sept 1944

Gunnery range tests at 6'x6' targets. Two Sherman Fireflys were used.

400 yds

APC hit 90.5%

APDS hit 56.6%

600 yds

APC hit 73.0%

APDS hit 34.2%

800 yds

APC hit 57.3%

APDS hit 21.9%

1000 yds

APC hit 45.3%

APDS hit 14.9%

1500 yds

APC hit 25.4%

APDS hit 7.1%

The report concluded:

useful range of APC ammunition was 900 yards while that of APDS was only 450 yards.

US tests at Isigny: 20-21 August, 1944

Targets were 3 Panther tanks at varying ranges from 200 yards to 600 yards.

On this basis all twenty-two (22) rounds of 76mm HVAP, T4, and all twenty-three (23) rounds of 17pr APCBC hit the target. Only one (1) of eight (8) rounds of 76mm APC, M62, which fell short attempting to hit the nose, failed to hit the target. Forty-two (42) rounds of 17pr sabot were fired, and only 57% (24 rounds) were hits.

[thejetset]

Fun stuff, eh?

Now, put 4 or 5 of those KT's up on a small rise, partially hull-down. Start a battalion of Shermans about 3 or 4 kms out, all on open ground. Have the Shermans try to close. I demand at least 10 runs of this test.

(Then, to be fair, have the KT's run out of gas. How well do they fight the next day?)

Bring in the P-47's!!!!!

[dieseltaylor]

Those figures make my testing of Shermans firing at 1700+ metres look somewhat exceptional. This is from the War Office and I assume the 90% zone refers to an area in which 90% of all the shots fell, interesting that more propellant increased the area:

WO 291/146 Dispersion of M48 HE shell from 75mm M3 gun in Sherman

M4A4.

• 90% zone of the shell, at the following ranges:
  Range (yds) Charge Vertical (feet) Horizontal (yards)
  1000 -- Normal ------ 3 ------- 35½
  2000 -- " ---------- 8½ ------- 46½
  3000 -- " --------- 18 ----- -- 56
  4000 -- " --------- 39 -- ----- 83½
  1000 -- Super ----- 2½ ------- 59
  2000 -- " --------- - 7 ------- - 67
  3000 -- " -- ------- 13 -- ----- 66½
  4000 -- " --------- 27½ ------ 82½

[Lee_Vincent]

I played the German, which was I was Micro managing his shots.

Shermans killed -Tiger killed

2-0 KT damaged gun, pulled out of action

1-0 abandoned good tank

2-0 abandoned good tank

5-0

1-0 kt damaged gun, pulled out of action

0-1 first 2 enemy shots penetrated and he was dead

3-0 lost 2 crew men and pulled out of action

1-0 KT damaged gun and then abandoned

0-1 lost weapon control then killed

5-0

total 20 fireflies lost, Two King Tigers lost, 3 abandoned, 3 pulled out of action

Old Test was simply, One King Tiger vs 5 Fireflies at over 500 Meters apart.

on real time , Warrior setting. Veteran crews except for the Tiger, I gave him a crack unit.

Results

If I played the German, which was I was Micro managing his shots.

Shermans killed -Tiger killed

1-1

5-0

5-0

5-0

1-1

total 17 fireflies lost, Two King Tigers

Playing the allied side, Which I had to do nothing. ( only the King Tiger did stupid things when the AI manages it.)

3-1

1-1

1-1

0-1

1-1

Total 6 fireflies lost, 5 King Tigers

Seems to be mostly a useful and revealing test on the AI aside from anything else.

[slysniper]

From UK Warrant Office Reports WO 291/1263 and WO 165/135, 22 Sept 1944

Gunnery range tests at 6'x6' targets. Two Sherman Fireflys were used.

400 yds

APC hit 90.5%

APDS hit 56.6%

600 yds

APC hit 73.0%

APDS hit 34.2%

800 yds

APC hit 57.3%

APDS hit 21.9%

1000 yds

APC hit 45.3%

APDS hit 14.9%

1500 yds

APC hit 25.4%

APDS hit 7.1%

The report concluded:

useful range of APC ammunition was 900 yards while that of APDS was only 450 yards.

US tests at Isigny: 20-21 August, 1944

Targets were 3 Panther tanks at varying ranges from 200 yards to 600 yards.

On this basis all twenty-two (22) rounds of 76mm HVAP, T4, and all twenty-three (23) rounds of 17pr APCBC hit the target. Only one (1) of eight (8) rounds of 76mm APC, M62, which fell short attempting to hit the nose, failed to hit the target. Forty-two (42) rounds of 17pr sabot were fired, and only 57% (24 rounds) were hits.

ouch, I do not need to run test to know the game just in general does not reflect these numbers.

[slysniper]

Seems to be mostly a useful and revealing test on the AI aside from anything else.

Well, keepin mind, if you are playing Wego PBEM, that AI will take over a unit very often, thus you will see that tank doing the same thing and not be able to do nothing about it til that next minute mark

[hoolaman]

ouch, I do not need to run test to know the game just in general does not reflect these numbers.

To be fair (thought it is no justification) the accuracy of normal AP ammo in the game is vastly more accurate than that too. At 800m I see first round hits time after time and nearly 100% accuracy. This is at tank size targets that are a bit bigger, but still...

[Vanir Ausf B]

Yes. The British tests were against a target 6'x6', which is much smaller than the front of a King Tiger. The US tests were against Panthers and you see much higher ABCBC accuracy there.

The real issue is the relative accuracey of APDS. In reality, 17 pdr APDS ammo was almost useless past about 500m. If the APDS in the game has the same accuracy as the APCBC ammo then your Fireflys are essentially using 1960s-era technology :confused:

[JonS]

From UK Warrant Office Reports WO 291/1263 and WO 165/135, 22 Sept 1944

That'd be 'UK War Office'.

[Vanir Ausf B]

Oops. I've actually had a hard time finding the original docs online, so I've had to rely on portions transcribed elsewhere, one of which was obviously miss-labeled.

[akd]

Quick test: 10 Fireflies (regular-normal) firing against 10 front-on Panthers at 800m. All 10 used APC rather than APDS. Only 3 achieved first round hits.

[Vanir Ausf B]

I'm not really concerned about APC accuracy. You may have to use King Tigers to force APDS use.

I ran across this old post by the estimable Rexford from 2001. It seems this was an issue in CMBO as well

CM really needs to model APDS inconsistency in terms of accuracy/penetration. Anything less is just not realistic. Once in a while APDS works like design, other times it doesn't. Our booklet will present enough data to estimate good/bad percentages.

And while they are at it, change the tungsten slope effects so they are in line with published test results (60 degree slope multipliers of 3.5 for APDS, 4.4 for HVAP), instead of home-brew concoction of 5.0 in CM.

If CM crew is dedicated to quality, the inconsistent quality and true slope effect of APDS should be addressed.

http://www.battlefront.com/community/showthread.php?t=28220&page=2

[akd]

Sorry, but statements like this are being made in the thread:

To be fair (thought it is no justification) the accuracy of normal AP ammo in the game is vastly more accurate than that too. At 800m I see first round hits time after time and nearly 100% accuracy. This is at tank size targets that are a bit bigger, but still...

[Vanir Ausf B]

Fair enough. And if someone wants to test 17 pdr ABCBC as well I'm all for it. But as I pointed out to hoolaman, you can't compare the UK test numbers directly to CM because the British were shooting at targets significantly smaller than a Panther tank.

[Vanir Ausf B]

Some of those old CMBO threads are a gold mine of information.

I suggest you take a look through the gunsights which were issued to British tanks equipped with the 17pdr during WW2. Whether you look at the:

No. 43 x3 L Mk.I (Sherman C only - Firefly)

No. 43 x3 ML Mk.I (1st 23 A30 Challengers only)

No. 43 x3 ML Mk.3 (A30 Challenger)

No. 43 x3 ML Mk.3/1 (Sherman C - Firefly)

you will see one common feature. None of these sights have any markings/graticules/range scales for APDS ammunition.

http://www.battlefront.com/community/showthread.php?t=28220&page=2

[Vanir Ausf B]

There is definitely enough evidence to support a reasonable failure rate with APDS, but my understanding is that a bad shell would be a spectacular failure like a dud ATGM curling away, but a good shell should be dead straght.

What proportion of duds vs winners? I don't know where to start with that one.

My continued reading supports your idea that it was mostly an all-or-nothing situation.

Rexford:

Good performing APDS is a gem, worth wading thru all the bad sabots and missing gun sight lines and in-the-way muzzle brakes and everything else.

Firefly APDS fans demand better slope effects, reduced dependability and less accurate sabot!!!! This way it's exciting like Las Vegas, where one loses miserably or wins like a million!

http://www.battlefront.com/community/showpost.php?p=287442&postcount=30

As Conall pointed out, sabots banged against muzzle brake as round left barrel or sabots clung too long on one side, throwing round off its' path. Throw in gun sights that went out of adjustment or didn't have APDS calibration and things keep getting worse.

http://www.battlefront.com/community/showpost.php?p=287438&postcount=26

[Guest]

ouch, I do not need to run test to know the game just in general does not reflect these numbers.

You don't know. You may *feel* the game in general does not reflect those numbers. You do need to run tests to know. Quite a lot of them, unfortunately.

To be fair (thought it is no justification) the accuracy of normal AP ammo in the game is vastly more accurate than that too. At 800m I see first round hits time after time and nearly 100% accuracy. This is at tank size targets that are a bit bigger, but still...

But I *don't* get first round hits time after time and with nearly 100% accuracy. In fact I rarely hit consistently outside of 500 meters. Aren't anecdotes and confirmation bias fun? But not terribly useful.

Guys, usually I'm quite level-headed about stuff like this. But unfounded hyperbole doesn't sell this as a bug. It sells it as unfounded hyperbole. If you want to run tests, do. If c3k can run exhaustive tests, let him. He seems to really get something out of it. But try not to let threads devolve into "of course it stinks, because it stinks" thinking, or else there'll be a whole lot of chaff when it comes time to work out what this thread might actually mean bug-wise.

[Vanir Ausf B]

A fair point, Phil. I do intend to run tests to get specific numbers with regard to APDS. It's just a matter of getting the time. Soon...

[Vanir Ausf B]

I have some results. It's not a very large sample size, but I think it's enough to answer the question of APDS accuracy.

Test was 5 Firefly VC firing at 5 King Tigers at 500m. Only first shots were counted. I ran the test 14 times.

AP

Hits: 27

Misses: 2

APDS

Hits: 41

Misses: 0

[Guest]

First, thanks for running tests.

Unfortunately, while your results are interesting, this amount of testing is not exhaustive or even very indicative. Assuming you're controlling for variables, I would like to see perhaps ten times this number of shots to really consider it indicative. That still wouldn't be definitive, but it would be enough for us to pursue it. There's a reason c3k spends a week setting up and running tests; a relatively small number of shots doesn't tell us enough.

Also, it would be good to know what the parameters of the your test are in more detail. Against stationary King Tigers, even a decently well-crewed Firefly with a straight shot should hit quite often at 500 meters. That's a big target, at fairly short range for a decent tank and crew.

[akd]

I have some results. It's not a very large sample size, but I think it's enough to answer the question of APDS accuracy.

Absolutely not. This question is much more complex than you are suggesting. There are two major problems:

1. There are operational research documents that contradict the one you posted in this thread, with results showing equal accuracy for APCBC and APDS at certain ranges and results showing greater accuracy for APDS. However, I don't think any single one of these documents is the "right" one; this simply highlights that there is a complex issue of inconsistency at play here. This is discussed in depth in the thread you linked. In particular, read the very last post in that thread.

2. A higher velocity round can be both less precise and more accurate than a lower velocity round where we define accuracy as probability of a first round hit on a target at unknown range. This is because the flatter trajectory compensates for range errors. You cannot simply state broadly that APDS is less accurate than APCBC, particularly against a large target at short range.

I have another document with a table that illustrates this well (but unfortunately I only have a scan of a single page and don't know what the actual source, but it is dated December 1944). The table gives the range at which there is a 50% chance of a first round hit on hull-up tank (allowing for typical range errors):

17pdr APCBC = 1000 yards

17pdr DS = 1100 yards

Next the range at which there is a 50% chance of a hit with subsequent shots is given:

17pdr APCBC = 2000 yards

17pdr DS = 1300 yards