American and British Stuart difference

[Thin Red Line]

I couldn't find any detail about the following in the archives : there is a difference beetween British Stuart V and American Stuart M5A1 : the later has a far higher rate of fire.

Actually, i came to ask this question to myself because I have currently a Stuart V in a game who, although neither damaged or shocked and engaged in combat vs infantry , is not using its 37mm HE (he tried unsuccessfully its AP against a KT at 600 m and managed to survive). In other games my US Stuarts fire like hell at every ennemy unit and i find them excellent.

Was the Stuart V gun so long to reload or difficult to handle ? Why such a difference with the US version ?

[Mattias]

Good question Thin. The British vehicle is a M3A3 (provided BTS intended to portray the Stuart V and not an earlier model) and, obviously, the US is a M5A1 but as I understand it the differences between these two vehicles are not of the nature that could explain the different ROF's.

I don't know really, maybe there is some kind of error in CM here, but looking in Chamaberlain/Ellis book and Crismons big "U.S. Military tracked vehicles" I can't find any reason for giving the Stuart V a glacis plate angled at only 20 degrees when it looks almost the same as that of the M5A1.

There are a few differences between the M3A3 and the M5A1 in RL but the former seems to have been a bit short changed in CM...

What does the Stuart aficionados say?

M.

[ March 04, 2002, 05:11 PM: Message edited by: Mattias ]

[flamingknives]

Aren't M3 series tanks the ones with a 75mm howitzer in the hull? Used extensively in the desert IIRC.

As for not firing, from what I've experienced, that could be some kind of AI bug. In a recent QB I had a platoon of regular PzGren. who refused to engage infantry at less than 100m, despite having nigh on full ammo and not being suppressed.

That's war I guess

[Pzman]

Originally posted by flamingknives:

Aren't M3 series tanks the ones with a 75mm howitzer in the hull? Used extensively in the desert IIRC.

As for not firing, from what I've experienced, that could be some kind of AI bug. In a recent QB I had a platoon of regular PzGren. who refused to engage infantry at less than 100m, despite having nigh on full ammo and not being suppressed.

That's war I guess

The M3 medium thank is the one you are thinking about. We are talking about the M3 light tank.

[The ol one eye.]

Maybe it was time for tea and crumpets?

[MikeyD]

I don't know if BTS designed these problems in, but not all Stuarts are created equal. Early production vehicles had the coaxial gun sight too close to the gun (a problem shared by the early M8 Greyhound and the Russian JS-2). This was fixed on later vehicles, you can spot the gunner's sight further away in vehicle photos.

also, some types of Stuart had the 37mm gun shoulder-aimed instead of the more stable handwheel traverse (a problem shared by early 6 pounder anti-tank guns). Shoulder-fired meant the kick would knock the gun off target every time and the gunner would have to reaim, slowing down acquisition time.

So a slow-firing Stuart and a fast-firing Stuart is a possibility.

[Mattias]

Mikey,

Sounds like exactly the kind of thing that could influence the ROF, or be portrayed by giving it a lower ROF to be exact. What makes me wonder though is the fact that the main gun was gyro stabilised as early as in the Stuart M3A1. Would a shoulder aimed weapon really be stablisied?

M.

[Tanaka]

I think by mid-44 the U.S. 37mm gun had a canister round, like a giant shotgun shell, maybe it hasn't anything to do with what is being described on this topic, but anyway, here it stays a small reminder

[ March 04, 2002, 05:35 PM: Message edited by: Tanaka ]

[John D Salt]

Originally posted by MikeyD:

[snips]

also, some types of Stuart had the 37mm gun shoulder-aimed instead of the more stable handwheel traverse (a problem shared by early 6 pounder anti-tank guns). Shoulder-fired meant the kick would knock the gun off target every time and the gunner would have to reaim, slowing down acquisition time.

[snips]

Eh? How on earth would the use of handwheel traverse have any effect at all on trunnion jump?

As to the 6-pdr, all 6-pdrs in British service used free (shoulder) traverse. I have never heard it mentioned as anything other than a positive feature.

The Americans, adopting and adapting the basic design as the 57mm gun M1, replaced this with handwheel traverse. The MIA2 and all subsequent American models returned to free traverse, "in the light of experience" according to Hogg's "British & American Artillery of WW2".

All the best,

John.

[Michael Emrys]

Originally posted by Tanaka:

I think by mid-44 the U.S. 37mm gun had a canister round, like a giant shotgun shell, maybe it hasn't anything to do with what is being described on this topic, but anyway, here it stays a small reminder

As I recall, BTS has stated that the canister round is not in the game at all.

Michael

[kmead]

I believe MikeyD meant to say the elevation was a shoulder mount not the traverse.

The M3A3 was an updated version of the M3A1, it adopted a sloped glacis and side hull plates. It also saw the introduction of hull top hatches for the driver and radio operator. It really was a much better looking machine and regrettably was not produced in numbers. It was superceeded by the M5 series vehicles that were simpler to produce and basically just as effective armor wise in combat.

From : www.wwiivehicles.com

M3A3: Standardized in August 1942, and classified as Limited Standard in April 1943.

M3A3: Had an improved turret with a bulge in the rear for the radio installed. Three additional periscopes are installed.

The hull was redesigned with all welded one piece hull front. The front plate was extended which allowed for more room for storage and improved the safety for the driver and assistant driver. The driver's hatches are moved to the top of the hull. Periscopes are installed to provide vision for the driver and assistant driver. The sponsons were extended to the rear and this allowed for more gasoline and ammunition storage. A storage box is added at the rear of the hull.

A sand shield is extended over the top of the suspension.

Additional improvements included easier steering, improved fire protection and ventilation, detachable head lamps, and a detachable windshield. A Combination Gun Mount, M44, with a telescope was installed.

Phased out of production in 1943.

[ March 04, 2002, 11:07 PM: Message edited by: kmead ]

[Mattias]

Originally posted by kmead:

It really was a much better looking machine and regrettably was not produced in numbers.

3427 is low numbers? What kind of numbers where the other models produced in?

M.

[kmead]

The M3, M3A1, and M3 Hybrids totaled nearly 19,000 machines from May 1941 to Jan of 1943. The M3A3 was produced for four months for a total of 3427. The M5 and M5A1 were produced from 1942 to 1944 and 8,800 of that design built. All of the M3/M5 vehicles were replaced by the M24 Chaffee which was produced in fairly small numbers as well, @4400 total. So yeah, a fair number of M3A3s were produced, most went to the British (2/3).

[Thin Red Line]

Thanks everybody for the (as always) exhaustive info.

Actually this light tank IS engaging ennemy, but only with MGs. Not a big difference you might say but hey...

[Ex Bellator]

I may have missed it but have we found out why the British Stuart is given a 'Slow ROF' in it's unit data? I'm still interested.

I ran a quick test with a US and a British Stuart firing 50 AP rounds at King Tigers. The tanks were Regulars, and I wondered how much slower a 'Slow ROF' really would be.

The US Stuart fired 10 rounds per min, the British Stuart 8 rounds per min. Not that much slower really, but there is a difference. C'mon grogs - put this grog wannabe out of his misery

[Mattias]

There has been some looking Rex but sometimes BTS walks in mysterious ways

M.

[gatpr]

I'm curious about the 37mm canister, or really I'm curious about why it's not in the game. Could comeone please enlighten me? I thought it was a very important piece of ammo especially in the Pacific.

[Michael Emrys]

Originally posted by gatpr:

I'm curious about the 37mm canister, or really I'm curious about why it's not in the game. Could comeone please enlighten me? I thought it was a very important piece of ammo especially in the Pacific.

AIR, BTS' excuse on this point was that at the time of release of the game, no information had turned up to verify the round's use in the ETO. Such documentation later turned up.

As an aside, it's also somewhat regrettable that white phosphorus is similarly not modeled.

Michael

[Tanaka]

Originally posted by Rex_Bellator:

I may have missed it but have we found out why the British Stuart is given a 'Slow ROF' in it's unit data? I'm still interested.

I ran a quick test with a US and a British Stuart firing 50 AP rounds at King Tigers. The tanks were Regulars, and I wondered how much slower a 'Slow ROF' really would be.

The US Stuart fired 10 rounds per min, the British Stuart 8 rounds per min. Not that much slower really, but there is a difference. C'mon grogs - put this grog wannabe out of his misery

Hmm... I wonder if there is more then tea into it

Some technical explanation on this one would be appreciated…

[Thin Red Line]

The said Stuart finally decided to use that not so much slow ROF gun now.

Question still pending though.

The grog wannabe

[flamingknives]

IIRC the pre/early war British cruiser tanks had the main gun (usually a 2pdr) mounted in the turret with no elevation mechanism. The gunner would stand in the turret, with his legs slightly bent, holding the gun. In effect, he would act as some sort of biological gyrostabiliser

[gunnergoz]

I did my Groggy duty and looked up the M3A3 and M5/M5A1 tank data in Hunnicutt's STUART A HISTORY OF THE AMERICAN LIGHT TANK. According to Hunnicutt (probably the best American tank engineering historian who's books are invaluable to us grogs), both tanks used the identical 37mm Gun M-6 in Combination Mount M-44 in the M3A3 and M5A1 and Combination Mount M-26 in the M5. The gun is uniformly rated at a maximum rate of fire of 30 ROUNDS PER MINUTE. The differences in gun mounts were minimal and did not impact operation of the weapon. So, if you ask me, BTS has made a distinction in the tank models' where none actually existed.

BTW, I recognize that ROF at 30 RPM would be probably impossible to attain operationally, but I'd venture to guess that a motivated and trained crew could possibly crank out 12-15 RPM in a pinch. The only trouble is, the commander would have to give up commanding to focus upon loading the piece for the gunner, as there was no loader in this series of tanks. And what would be the benefit of having no one to point out targets to the gunner? So, practially speaking, the gunner has to load the weapon too, thus taking his eyes of the sights and having to take time to reaquire the target.

It's too bad they couldn't fit the automatic version of the 37mm gun into these tanks...while the muzzle velocity might be a bit less, it would be easy to load a magazine adapted to the tank turret that could hold perhaps 50-60 rounds. That would have been a Spahpanzer Killer Deluxe!

[Tanaka]

Originally posted by gunnergoz:

...and looked up the M3A3 and M5/M5A1 tank data in Hunnicutt's STUART A HISTORY OF THE AMERICAN LIGHT TANK. According to Hunnicutt... both tanks used the identical 37mm Gun M-6 in Combination Mount M-44 in the M3A3 and M5A1 and Combination Mount M-26 in the M5....The differences in gun mounts were minimal and did not impact operation of the weapon. So, if you ask me, BTS has made a distinction in the tank models' where none actually existed...

Hmm... That coincides with my view and information regarding the gun mounts on both these light tank versions.

Since I’ve looked far back as the 2000 forum archives (inclusive) and didn’t find any discussions regarding the ROF difference, it would be nice if some one could come up with the BTS source of information... basically just one idea/fact that backs up the game information.

Apart from the technical stuff, I’ve used the UK version of this tank quite a few times in the game, the 37mm gun even with the “slow ROF” factored in, can take well care of it self… Of course, a little more speed wouldn’t do no harm, only to those side and rear German AFV armors

[Brian]

No one seems to have considered the most obvious difference - doctrine.

American tanks had gyrostabilisers. American gunners were trained to use them. While many misused them and they often burned out, they supposedly conferred a superior ability to fire and hit the target (there is some doubt on that one).

British tanks often had the gyrostabilisers removed and British doctrine was not to use them anyway. Lack of a stabiliser would decrease the rate of fire.

Instead of looking in books about American tanks and how they were designed and built (ie Hunnicutt, which is BTW an excellent source for most things), you should IMO be looking in British books about how the tanks were employed and how the British Armoured Corps/Cavalry Regts were trained and fought.

BTW, speaking of Hunnicutt, I'd suggest his 30 rounds a minute was in a stationary vehicle on a range with a well trained crew. No way that rate of fire could be maintained in a vehicle moving at speed over rough ground, in the middle of an engagement IMO.

[Tanaka]

Originally posted by Brian:

...American tanks had gyrostabilisers. American gunners were trained to use them. While many misused them and they often burned out, they supposedly conferred a superior ability to fire and hit the target (there is some doubt on that one).

British tanks often had the gyrostabilisers removed and British doctrine was not to use them anyway. Lack of a stabiliser would decrease the rate of fire...

Hmm... I could bet CM had a different modifier for the gyrostabilizer factor, other then "slow ROF"... "gyrostabilizer" maybe

So, what you are basically saying is:

In CM, tanks with "gyrostabilizer" get a positive accuracy bonus, while tanks without it on top of not getting this bonus, also get a negative "slow ROF" bonus. I wonder what a German tank commander of the 2nd WW with the "fire only when stop" doctrine would have to say ?!