# Fully tracked APCs for ww2: not worth it; or, why they didn't think of those?



## tomo pauk (Apr 28, 2012)

...I'm thinking about the vehicles that should provide a protection, for the mounted infantry, from artillery shrapnels and LMG fire. Sporting also roof armor to protect from light mortar fire, hand grenades, fire from the windows of the high buildings etc. The APC would be something along the lines of M-113, other technicalities shared with the AFVs/tanks from the era. 

What's your take?


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## pbfoot (Apr 28, 2012)

the Kangaroo although lacking in the overhead armour certainly must count as an APC
http://en.wikipedia.org/wiki/Kangaroo_(armoured_personnel_carrier)


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## davebender (Apr 28, 2012)

Full track has nothing to do with overhead armor. It's about how much of the vehicle weight is carried by tracks vs how much weight is carried by the front tires on a half track. Carrying all or most of the weight on tracks increases cross country mobility.


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## Shortround6 (Apr 28, 2012)

Bren carriers?

No overhead protection though. 

Most nations had enough trouble trying to make enough tanks. 

making full track APCs is not that easy. While the armor is thinner you still need the tracks, suspension, transmission/steering gear. 

Even M-113s were never intended to be used _IN_ the battle but to get the infantry _TO_ the battle.


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## davebender (Apr 28, 2012)

I disagree. Making full track APCs is no more difficult then making full track tanks or SP artillery. The issue is resource allocation. 

A single German mechanized infantry company requires a minimum of 12 APCs.
3 companies per battalion.
9 battalions per division.
.....Add APCs for support elements (SP flak, SP signal, SP mortars, armored ambulance etc.) and you need 400 to fully mechanize an infantry divsion.

100 mechanized infantry divsions require 40,000 APCs @ 22,000 RM each (for Sd.Kfz.251) and a whole lot of fuel (plus fuel trucks). Full track might bump the price up to 30,000 RM per APC but that makes little difference. Nobody can afford to mechanize this many infantry divisions and keep them supplied with fuel.


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## Glider (Apr 28, 2012)

This brings a question re the M3 halftrack. Did it bring the benefits of both types of traction or did it bring the worst parts of both? Having gone to the cost of building it why didn't they extend the tracks and get rid of the wheels.

Any ideas?


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## Shortround6 (Apr 28, 2012)

Mr Bender is correct, the "Making full track APCs is no more difficult then making full track tanks or SP artillery. The issue is resource allocation. "

The point was that full tracked APCs are not going to be much cheaper or easier to make than a tank or SP gun of similar weight and if you can't make enough of them then APCs are going to be hard to come by. 

Mr. Bender also as a point about fuel. Full tracked vehicles, as a general rule of thumb, have twice the rolling resistance of a wheeled vehicle which means for a given weight the tracked vehicle will need twice the fuel to go the same distance at the same speed. Given WW II technology, track life is also fairly short. 3000 miles on a set of tracks was considered almost miraculous. Some tanks went through tracks in as little as 600 miles. Full tracked APCs offered tactical mobility but came up short in strategic or grand tactical mobility. 

The American Half track used a rubber band track, no links, just a big rubber band with steel cables inside. It did offer lower ground pressure than a wheeled vehicle but trying to extend the size of the tracks/bands may have been a problem. As would trying to steer with them. 

I have no experience with them but I used to drive a 68,000lb fire truck with three axles, the rear two powered, it chewed the rear-most axle tires up some fierce, under 8,000 miles. Lots of city driving and sharp corners. I would imagine trying to use rubber band tracks to generate the turning motion driving them at different speeds and scrubbing as they turned would chew up the tracks. Granted this is not an issue for off road use but how much of the APCs life would be spent on roads?


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## Juha (Apr 28, 2012)

Glider said:


> This brings a question re the M3 halftrack. Did it bring the benefits of both types of traction or did it bring the worst parts of both? Having gone to the cost of building it why didn't they extend the tracks and get rid of the wheels.
> 
> Any ideas?



M3 was more like 4x4 armoured truck with rear wheels substituted by a track system, fairly cheap system, German armoured h/ts were in essence fully tracked vehicles with longer forward body under which there were unpowered steerable front wheels with the complications and expenses of fully tracked vehicle but better ground loading than M3. IIRC SdKfz 250s/251s used system where gentle curves were handled with the steerable front wheels but any steeper curves needed normal fully tracked vehicle steering which meant complicated and costly steering mechanism.

Juha


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## Glider (Apr 29, 2012)

Thank you both, I have often wondered about that


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## Denniss (Apr 29, 2012)

If my memory serves right the german halftracks used truck chassis as well. but they may have modified them more than other countries.
Halftracks were not only built because they were comparable cheap, they could also use truck chassis manufacturers to produce tracked vehicles, no need to bother tank manufacturers with another task.


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## tomo pauk (Apr 29, 2012)

Thanks for the inputs 

Some questions:
How good were the half-tracks in following the tanks, off road?
Would it been better to have infantry traveling inside an APC, or as a tank-riders?
How frugal was building using the M3/M5 lights in 1943/44, 2 pdr tanks in 1942-43, 6pdr tanks in 1944, Pz-38(t) in 1942? 
Ditto for Centaur, Valiant, Covenanter?
What was the cost of the Universal Carrier?
What happened with the tooling for the Vickers light tanks?
Weren't the light tanks mostly built away from dedicated tank factories?


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## GrauGeist (Apr 29, 2012)

The Germans used a light Soviet tank chassis to modify the Opel truck and as a result, the Maultier half-track proved to be for more reliable over open/rugged terrain than the original all-wheeled configuration...


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## pbfoot (Apr 29, 2012)

I m3ntioned the Kangaroo earlier was it the 1st tracked APC as we know it today it is fully tracked and found to be very useful although of a relatively short career from Falaise to VE day
here is the Wiki blurb on the Regiment which was the only regiment formed overseas in WW2
1st Canadian Armoured Carrier Regiment - Wikipedia, the free encyclopedia


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## GrauGeist (Apr 29, 2012)

That Kangaroo was the M7 Priest, wasn't it?


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## pbfoot (Apr 29, 2012)

GrauGeist said:


> That Kangaroo was the M7 Priest, wasn't it?


one version


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## tomo pauk (Apr 29, 2012)

pbfoot, I'm fully aware of the Kangaroos. An army being awash with Carriers, decided to use an redundant tank/SPG hull (= more horizontal protection) - that might point that a heavy APC had it's place at the battlefield. Sure enough, a LMG- and splinter-proof (light) APC would be fine for an army trying to adopt a really combined arms layout?

GG, there were Ram- and Priest kangaroos, depending upon the AFV that was converted. There was also a Churchill Kangaroo (prototype?).
What I'd like to see is the Grant Kangaroo (unless making a dedicated APC), converted from the early versions sporting the side doors, LMG turret, steel sheet covering the roof (37mm turret deleted, along with 75mm, it's former position receiving an armor sheet).


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## Shortround6 (Apr 29, 2012)

tomo pauk said:


> Thanks for the inputs
> 
> Some questions:
> How good were the half-tracks in following the tanks, off road?
> ...



The medium tanks were too heavy to make really good APCs but they were available. Light tanks (of the WW II variety) make lousy APCs because they are too small. An APC needs to hold a normal squad or close to it. Using two or even three vehicles to move 10-12 infantry men is not only wasteful but gets really confusing at dismount time. 

Extending the hull on some tanks can be done but only works so much. If the length of track on the ground exceeds the distance between the tracks by more than about a 1.8:1 ratio the vehicle becomes hard to steer. 

Converted tanks are less than ideal because the rear engines mean the infantry have to dismount and mount over the sides. It was done but it is certainly less than ideal and causes injuries. 

The Half tracks could keep up pretty well and tank riders are a really bad idea. Better than no infantry but carrying your infantry on surfaces that bullets and shell fragments can ricochet from may actually increase casualties. The Russians may have accepted such casualties but the western nations would not. Please note there is a big difference between giving infantry a ride up to the front or in rear areas and carrying them into gunfire on the tanks. 

The continued production of some light tanks (in fact a lot of them) was a waste of resources. But an armored division only had about 100-300 tanks depending on army and time. You need at least 45-50 APCs for even a small Battalion of 3 companies each with 3 platoons allowing for headquarters units and such. 

It also does you no good to have tanks and armored infantry if the artillery cannot keep up. Tracked artillery was probably more important than tracked infantry.


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## GrauGeist (Apr 29, 2012)

Shortround6 said:


> ...It also does you no good to have tanks and armored infantry if the artillery cannot keep up. Tracked artillery was probably more important than tracked infantry.


And air support!


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## tomo pauk (Apr 29, 2012)

Good call, GG. One still need artillery as a ground pounder, every bit.



Shortround6 said:


> The medium tanks were too heavy to make really good APCs but they were available. Light tanks (of the WW II variety) make lousy APCs because they are too small. An APC needs to hold a normal squad or close to it. Using two or even three vehicles to move 10-12 infantry men is not only wasteful but gets really confusing at dismount time.



Maybe you're misuderstood my mentioning of all the tanks in the above post - I'm not saying that those were to be converted into APCs (not my 1st call anyway), but to point into the fact that some armies were awash in tanks, yet had (almost) none of well protected APCs that might carry infantry to within hundreds of meters close to the front line. Under 'well protected', I assume that a gun equal to 50mm or better was needed to tackle those.
Regarding to the number of vehicles to carry a squad, the U. Carrier carried 5 crew, driver included. Falls well within the 'lousy APCs' group? 



> Extending the hull on some tanks can be done but only works so much. If the length of track on the ground exceeds the distance between the tracks by more than about a 1.8:1 ratio the vehicle becomes hard to steer.



Guess you're right about the ratio. The Cromwell -> Challenger conversion was noted as not as maneuverable as the Cromwell itself.



> Converted tanks are less than ideal because the rear engines mean the infantry have to dismount and mount over the sides. It was done but it is certainly less than ideal and causes injuries.



Agreed 100%. That's why I'm talking about a 'classic' APC as a better solution.



> The Half tracks could keep up pretty well and tank riders are a really bad idea. Better than no infantry but carrying your infantry on surfaces that bullets and shell fragments can ricochet from may actually increase casualties. The Russians may have accepted such casualties but the western nations would not. Please note there is a big difference between giving infantry a ride up to the front or in rear areas and carrying them into gunfire on the tanks.



When mentioning the tank riders, I'm trying to point out that an APC would be also good for Soviets in ww2. Despite all the saying about the USSR as having plenty of manpower, saving thousands of infantryman (that can grow some experience, instead being mowed down by the mortar, artillery MG fire) seems like a good thing.



> The continued production of some light tanks (in fact a lot of them) was a waste of resources. But an armored division only had about 100-300 tanks depending on army and time. You need at least 45-50 APCs for even a small Battalion of 3 companies each with 3 platoons allowing for headquarters units and such.



All fine, we better start producing the APCs ASAP - if the infantry in the units mentioned are to be riding at the Carrier, the number of vehicles required skyrockets 



> It also does you no good to have tanks and armored infantry if the artillery cannot keep up. Tracked artillery was probably more important than tracked infantry.



SP tracked artillery was present in major armies. Plus, many of them towed their guns by half tracks or fully tracked vehicles; such arty did not needed to close within hundred of meters to the enemy. The APC needed to closely follow the tanks or assault artillery were not that present, though.


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## davebender (Apr 29, 2012)

> M3 was more like 4x4 armoured truck with rear wheels substituted by a track system, fairly cheap system, German armoured h/ts were in essence fully tracked vehicles with longer forward body under which there were unpowered steerable front


I agree. The difference is obvious if you look at vehicle pictures.

Sd.Kfz.251 3/4 Track.




Track suspension carries most of vehicle weight and it's the same state of the art schachtellaufwerk suspension employed on Panther and Tiger tanks. Consequently troops and equipment in back have a relatively soft ride when moving cross country. Protective armor is nicely angled too. Vehicle may be steered using tracks. That's important for a combat vehicle as one or more front tires are likely to be shot out when bullets start flying. Amazingly enough this superior WWII era APC was also slightly less expensive then the U.S. made M3 Half track.





M3 Half Track.




Small track area in contact with ground made it essential to power the front wheels to obtain cross country mobility. However you were screwed if the front tires got shot out. Ride and armor protection were inferior to German made counterparts.


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## Juha (Apr 29, 2012)

IMHO they well presented the different armament ideas of Germany and USA. Germans tried to achieve technical superiority but theirs tended to be more complicated and US paid more attention to productively. And as in trucks, M3 had more powerful engine in fact it had 47% more power. US armoured divs had armoured h/ts to all their 3 armoured Inf Battalions, in German PzDivs usually only one of 4 PzGrenBattalions rode in Sd.Kfz 251s others were truck-borne.

Juha


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## GrauGeist (Apr 29, 2012)

The companies, White and Dodge, that manufactured the M3, also used engines that were already in production....namely engines that were used in trucks and busses, which helped keep the cost down.

Added: meant to say that the existing engines kept cost down AND production numbers up...


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## michaelmaltby (Apr 29, 2012)

"... Ride and armor protection were inferior to German made counterparts."


How many M3's can I have for one superior PanzerTraker Sd.Kfz.251, Mr. Bender ... 

MM


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## Shortround6 (Apr 29, 2012)

Mr. Bender still seems to be using the "official" exchange rate if he thinks that a Sd.Kfz.251 is cheaper than an M3.


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## Shortround6 (Apr 29, 2012)

tomo pauk said:


> Maybe you're misuderstood my mentioning of all the tanks in the above post - I'm not saying that those were to be converted into APCs (not my 1st call anyway), but to point into the fact that some armies were awash in tanks, yet had (almost) none of well protected APCs that might carry infantry to within hundreds of meters close to the front line. Under 'well protected', I assume that a gun equal to 50mm or better was needed to tackle those.
> Regarding to the number of vehicles to carry a squad, the U. Carrier carried 5 crew, driver included. Falls well within the 'lousy APCs' group?



Some of those tanks were mistakes, unfortunately for the British (and some other countries) they were not "awash in tanks" at the time they were being made. Some of the them were being cranked out in times of desperation when _good_ tanks were in short supply. 
If you are looking for an APC that is resistant to 50mm gun fire you need a 30 ton tank or better for starters. Which takes out just about all of the tanks mentioned. German Pak 38 could penetrate 61mm of vertical plate at 1000yds? 

The Bren carrier was not really supposed to be an APC, it was a scout vehicle or more properly a vehicle to carry an infantry scout section. It also provided mobility for company or battalion support weapons. It started as the Vickers carrier as in Vickers machine gun. It wound up carrying 3 in mortars although in some early versions the mortar could not be fired from the vehicle. It sure did beat men on foot lugging the barrel, base plate and bipod around, not to mention a quantity of ammo. Same with the Vickers gun. It provided mobility for a 100lb+ support weapon, a quantity of ammunition and it's crew that would not be able to keep on the battle field when carried on foot. 

Wiki gives as short over view: Universal Carrier - Wikipedia, the free encyclopedia



tomo pauk said:


> Agreed 100%. That's why I'm talking about a 'classic' APC as a better solution.
> 
> 
> > There were no 'classic' APCs in WW II although the concept isn't really that difficult, move engine and drive line to the front, put big door in back. However the difference between bullet and shell fragment proof and even 37-50mm proof is 10-15 tons. you jump from light tank components (even if you don't use the hull) to medium tank components.
> ...


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## davebender (Apr 29, 2012)

Sd.Kfz.10 / Sd.Kfz.250. About 21,000 produced @ 15,000 RM each. Light towing tractor / light APC.
.....Sd.Kfz.250 is APC version of the Sd.Kfz.10 towing tractor.
Sd.Kfz.11 / Sd.Kfz.251. About 25,000 produced @ 22,000 RM each. Medium towing tractor / medium APC.
.....Sd.Kfz.251 is APC version of the Sd.Kfz.11 towing tractor.

What's wrong with German production quantities or production costs? They compare favorably to the inferior U.S. M3 half track.


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## Shortround6 (Apr 29, 2012)

Just why is the M3 inferior? in which roles? 

Costs based on the "exchange rate" will tossed in the garbage unless you can explain how the Germans could produce the P-38 pistol at the same or lower cost as the US single shot, stamped sheet metal, smooth bore Liberator pistol.


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## DonL (Apr 30, 2012)

Sometimes I would wish more objectivety.

The US Army had a comparative test at 1943 between M3 and Sd.Kfz.251!
At this test the US Army stated that the Sd.Kfz.251 armour layout and in general the armour was much better then the M3, the cross country mobility was much better and also the cooling system was better under fire and more reliable.

The M3 was larger with more room, had the powered front suspension and a better mobility on streets. 

The M3 had very heavy losses at North Africa at the Battles of Kasserine beginning 1943), as the Wehrmacht was a little more competitive then 1944 or 1945



> How many M3's can I have for one superior PanzerTraker Sd.Kfz.251, Mr. Bender ...





> IMHO they well presented the different armament ideas of Germany and USA. Germans tried to achieve technical superiority but theirs tended to be more complicated and US paid more attention to productively. And as in trucks, M3 had more powerful engine in fact it had 47% more power. US armoured divs had armoured h/ts to all their 3 armoured Inf Battalions, in German PzDivs usually only one of 4 PzGrenBattalions rode in Sd.Kfz 251s others were truck-borne.



To me the coments are not objective. The M3 was 2 tons heavier then the Sd.Kfz.251, so the 47% more power is rubbish at the power to weight ratio 13,5ts to 16ts. Also I can't see that the Sd.Kfz.251 is overengineered or too expensive, when it had 2 tons less weight, because of a smaler room but a much better sloped armour layout. 
Why is here anyone thinking that the Sd.Kfz.251 is more expensive then the M3. Do you have any numbers?
Not all german equipment is overengineered and expensive!

Also the Sd.Kfz.251 was back in Production at 1958 as OT-810 at the czech republic to replace the BTR-152 and was in service till the 1980's. From all I have read from military experts the Sd.Kfz 251 was credit as a very successful and reliable construction.


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## Shortround6 (Apr 30, 2012)

I think I was being very objective. I did not state that the M3 _was_ superior to the Sd.Kfz.251. I asked how it was inferior. 

Both types had areas that they better in than the other. Especially for certain specialized roles. Perhaps the Sd.Kfz.251 was better overall but it takes quite a list to make the assessment and not picking just a few facts.

Which has the better trench crossing ability?
Which has the better vertical obstacle ability?
Which can climb a steeper gradient or restart on the steeper gradient?
Which has the better towing ability and are they being measured the same way? 

and so on. 

As far as cost goes the Sd.Kfz.251 used a more complicated armor layout. More pieces that meet in more complicated joints. It was better for protection. The Germans simplified later models to cut costs.

The German track system was more expensive. 

The American front axle was more expensive.

The German steering system was more expensive.


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## Shortround6 (Apr 30, 2012)

To get back OT.

a box carrier like a M113 big enough to hold 12 men was going to run 15-20 tons. This pretty much rules out using most of the smaller light tank engines. Like the British MK VI light tank or the German MK II engines and so on. Likewise the transmission/steering gear. Suspension may call for more than just an extra road wheel. 

The idea of an APC is a good one. It is just that few, if any, countries had the industrial capacity to make them in large enough numbers to equip more than a few divisions.

There is also a difference between an APC and IFV (infantry fighting vehicle). Infantry was _NOT_ supposed to fight from _inside_ the APC.


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## GrauGeist (Apr 30, 2012)

Let's not forget that the U.S. Marines used an armored transport LVT-1, called an AmTrac (amphibious tracked vehicle) that carried up to 24 personnel and a crew of 3.

There were several upgrades to the AmTrac, ending in the LVT-4, but it remained a stable workhorse throughout the pacific theater.


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## davparlr (May 1, 2012)

Half tracks

Some comparisons

(251/_M3_)
Weight (Tons) 8.7 _ 9.3_
Hp 100 _143-147_
Power to weight (hp/ton) 11.5 _15.8_
Speed (mph) 32 _45_
Armor, max (in.) .47 _.512_
Crew 2+10 _3+10_
Ground Clearance (in.) 12.6 _11_
Range (miles) 217 _200_
Max angle of climb degrees 24 _60 (30)_
Fording ability (in.) 19 _32_
Turning radius (ft) 36 _60 _ 

“Objectively” speaking it appears that the M3 is .6 of a ton heavier with 47% more hp giving it about a 37% better power to weight ratio. It also has 40% better speed capability, important if you want to keep up with Patton. Due to slanted armor, the 251 has better protection, but not a lot. Personnel carriage is basically even. The 251 has slightly better ground clearance which is important and slightly better range. In climbing ability, the M3 is better (there seems to be some conflict in data here as many site state it is 60 degrees and one 30. I believe in 30). Fording ability, important, is an advantage for the M3. Turning radius, also important is much better in the 251, most likely do to the use of track braking.

“Subjectively” speaking the two are very good halftracks with different characteristics, each show an advantage in important areas, the 251 in armor, ground clearance, turning radius, and general rough terrain ability. The M3 has advantages in power to weight, speed, climb angle and fording ability. In addition, both apparently soldiered on after the war with the M3 participating in the Israeli-Arab wars.

To state that one is significantly better and the other is … not stating “objectively”!



davebender said:


> Track suspension carries most of vehicle weight and it's the same state of the art schachtellaufwerk suspension employed on Panther and Tiger tanks.



Were there any post WWII tanks that adopted this “state of the art” suspension system? Maintenance on those inboard rollers must have been fun.



> Protective armor is nicely angled too. Vehicle may be steered using tracks. That's important for a combat vehicle as one or more front tires are likely to be shot out when bullets start flying.



All good comments



> Amazingly enough this superior WWII era APC was also slightly less expensive then the U.S. made M3 Half track.



To use your line


> The difference is obvious if you look at vehicle pictures.


Note the complex front end, the multi-angled armor, and the highly complex suspension system of the 251. It is indeed obvious that the manufacturing manhours would be significantly lower for the M3. After all, “it is only a commercial truck with armor attached, fairly cheap system”. I would bet that the American automobile industry was the most efficient in the world.



> Ride and armor protection were inferior to German made counterparts.



I suspect you have no idea how the M3 rides.



DonL said:


> Sometimes I would wish more objectivety.



That works both ways.



> The US Army had a comparative test at 1943 between M3 and Sd.Kfz.251!
> At this test the US Army stated that the Sd.Kfz.251 armour layout and in general the armour was much better then the M3, the cross country mobility was much better and also the cooling system was better under fire and more reliable.



I am sure armor was better. However, the M3 was faster, could ford deeper rivers, could climb more steep inclines, and high tail it on a decent road, so, I guess it depends on the terrain that is being crossed on which one is better.



> The M3 had very heavy losses at North Africa at the Battles of Kasserine beginning 1943), as the Wehrmacht was a little more competitive then 1944 or 1945



Inappropriate comparison. At Kasserine the M3 was missed used as an anti-tank vehicle with an inadequate anti-tank gun and when they confronted the Africa Corps tanks they were predictably massacred as was the American tanks and the inexperienced, poorly trained and incompetently led American soldiers. I am sure that under the same circumstances the 251 would have fared no better.



> To me the coments are not objective. The M3 was 2 tons heavier then the Sd.Kfz.251, so the 47% more power is rubbish at the power to weight ratio 13,5ts to 16ts.


You can see the power to weight ratio above. And, Speed is Speed. I don’t see any lack of objectivity. Data may be different but challenge the data not the objectivity of the poster.



> Also I can't see that the Sd.Kfz.251 is overengineered or too expensive, when it had 2 tons less weight


I don’t think the M3 is two tons heavier than the 251. Data is variable but my book “The Encyclopedia of Tanks and Armored Fighting Vehicles” shows the data I posted as does Wikipedia.


> , because of a smaler room but a much better sloped armour layout.
> Why is here anyone thinking that the Sd.Kfz.251 is more expensive then the M3. Do you have any numbers?


I don’t but horse sense tells another story.



> Not all german equipment is overengineered and expensive!


VWs were indeed cheap, simple and reliable. Nor is all German equipment superior to it allied counterpart.



> Also the Sd.Kfz.251 was back in Production at 1958 as OT-810 at the czech republic to replace the BTR-152 and was in service till the 1980's. From all I have read from military experts the Sd.Kfz 251 was credit as a very successful and reliable construction.


No doubt that the 251 was all you said. However, the M3 also continued successfully in service apparently as late a 2006. It is not a design to dismiss as inferior.


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## Denniss (May 1, 2012)

Please check your sources, you are mixing short tons with metric tonnes, the 251 weighted ~7.5 tonnes while the M3 weighted 9.3 tonnes


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## DonL (May 1, 2012)

> (251/M3)
> Weight (Tons) 8.7 9.3
> Hp 100 143-147
> Power to weight (hp/ton) 11.5 15.8
> ...



This numbers are incorrect for the Sd.Kfz.251!

Correct numbers after Walter J. Spielberger:

Weight: 7,4 t!
Power: 100PS
Power to weight (hp/t): 13,5PS/t
Speed: 52,5 km/h (32,6 miles)
Ground Clearance mm (in.): 320mm (12,6)
Fuel capacity: 160l
Range km (miles): 320km (200) / to my books range of the M3 was 282 km (175miles) with 230liter (60USg)
Fording ability (in.): 500mm (19,7)
Turning radius (ft) : 13,5m (44)


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## Shortround6 (May 1, 2012)

For US use the climb grade is actually a percent and not in degrees. the US half track will climb a 60% slope. that is a slope that rises 6ft for every 10 ft of horizontal difference. 

Please note that a 100% slope is 45 degrees. Also note that for a US vehicle to be rated at 60% the vehicle had to parked on a 60% slope, the engine turned off and then restartted, and then the vehicle had to start moving again on the 60% slope. There is/was a man made hill at Aberdeen proving grounds that was 60% on one side where this test took place. a safety cable was often routed over the hill to prevent accidents or rolling back too far. 

The US used two different engines in the halftracks. the normal engine was a 6.3liter six compared to the 4.2 liter six in the German halftrack. Torque is much more related to engine displacement than horsepower is. The alternate engine, used almost entirely for lend-lease was a 7.4 liter six of about the same peak power but lower revving. 

when comparing weights please check to see if they are "factory empty", combat ready or loaded. or something in between.

Being objective I would say the range is too close to call, unless this is a bar bet. 1953 US catalog of vehicles claims a range of 210 miles for the M3 on 60 gallons, speed and load not stated. Since the German half track falls in the middle of the highs and lows of the American claims and as we ALL KNOW " _YOUR gas mileage may VARY_ i would call this this one a draw. At best the German track gets 6% more range.


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## DonL (May 1, 2012)

> when comparing weights please check to see if they are "factory empty", combat ready or loaded. or something in between.



The weight of the Sd.Kfz.251 with armour, armament and fuel (combat ready) was 7,4t!
The payload was 1,1t.

Edit:

Maximum angle of driving 24 degrees
Later Versions had 7,5 t and a payload of 1,5t the maximal weight was 9t, with all equipment and soldiers!


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## tomo pauk (May 1, 2012)

Here are the two APCs based upon the T-26, made in 1933-35. Transporting 13 and 14 soldiers, respectively. Swedish PBV 301, based upon the license produced copy of the Pz-38(t), was carrying 2+8, but it looked far more a refined design.


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## davparlr (May 1, 2012)

Denniss said:


> Please check your sources, you are mixing short tons with metric tonnes, the 251 weighted ~7.5 tonnes while the M3 weighted 9.3 tonnes


My reference does show the 251 and M3 weight in kg, 8500 for the 251 and 9472 for the M3, which still comes up to 37% more power to weight ratio. Of course I don’t really know if those are English kgs or American kgs.

The reference is English and the numbers are in long tons.



DonL said:


> This numbers are incorrect for the Sd.Kfz.251!
> 
> Correct numbers after Walter J. Spielberger:
> 
> ...



There is a lot of contradictory data available from reliable sources on both vehicles. As SR stated, range varies. However, if I take your data directly, what would you change in the statement I made except adding range (questionable) to the 251 advantages.

“Subjectively” speaking the two are very good halftracks with different characteristics, each show an advantage in important areas, the 251 in armor, ground clearance, turning radius, and general rough terrain ability. The M3 has advantages in power to weight, speed, climb angle and fording ability.”


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## tyrodtom (May 1, 2012)

I've got 3 books before me right now, and i've got more, but the 3 vary on the KFZ.251 weight a bit. 
Bk# 1 9.4 tons
Bk#2 8.4 tons
Bk#3 7.93 tons, or 8.74 tonnes they got tons and tonnes reversed. As some of us may.

There's the ton or short ton 2000 lbs, mostly a USA form of measurement
There's the long ton, 2240 lbs United Kingdom, Commonwealth, and the US Navy, just to confuse us all.
There's the metric ton, or tonne, or t, 2204 lbs, used by the rest of the world.

Anybody got a SD.KFZ.251? I've got access to some big scales.


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## Shortround6 (May 1, 2012)

Weights for the different models vary but the 1953 TM 9-2800-1 technical manual for Military vehicles gives the net weight of of the M3 halftrack (not the M3A1) as 15,500lbs, payload as 4500lbs and gross weight as 20,000lbs. Net weight is defined on page 1 of the manual as " Weight of the fully equipped vehicle in operating condition with fuel, lubricants, and water, but without crew or payload, unless otherwise specified." 

The M2A1 half track is listed at 14,600lbs net, 5000lbs payload and 19,600lbs gross. 

Max recommended towed load, cross country, is 4,500lbs but the British used them to tow 17pdr AT guns in the post war Army of the Rhine. maybe they had the 7.4 liter engine version?


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## davparlr (May 2, 2012)

Shortround6 said:


> Weights for the different models vary but the 1953 TM 9-2800-1 technical manual for Military vehicles gives the net weight of of the M3 halftrack (not the M3A1) as 15,500lbs, payload as 4500lbs and gross weight as 20,000lbs. Net weight is defined on page 1 of the manual as " Weight of the fully equipped vehicle in operating condition with fuel, lubricants, and water, but without crew or payload, unless otherwise specified."
> 
> The M2A1 half track is listed at 14,600lbs net, 5000lbs payload and 19,600lbs gross.
> 
> Max recommended towed load, cross country, is 4,500lbs but the British used them to tow 17pdr AT guns in the post war Army of the Rhine. maybe they had the 7.4 liter engine version?


 
Thanks, good data. Weight is always an issue with military equipment, especially aircraft. The big question is always "what does the weight include". That why I think "America's Hundred Thousand", recommended to me by Rerich, is such a treasured book. Too bad we don't have that kind of data on all the equipment.


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## Denniss (May 2, 2012)

I have (or have access to) several books about half tracks, most are vague with weights, give only one figure or have nothing at all.
The 251 Ausführung A seems to have started with an equipped weight (=net weight?) of just above 7 tonnes (7.8 tons) while the Ausführung D (last major version) hat 8 tons (~7.25 tonnes). Maximum weight is about 8.5 tonnes but the books I have don't state which Ausführung this figure applies to.

It's really a pain to have two imperial weight figures of the same name (ton/tons) but you never know which one is used unless specified (or you have to guess judging from where a book originates).


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## Shortround6 (May 2, 2012)

I don't know if the "net weight" of the American half tracks includes armament or not or if it includes ammunition. Some sources list 700 rounds of .50 cal ammo for about 210lbs not including the ammo cans plus 7000 rounds of .30 cal ammo for another 420lbs or so, not including cans. Up to 13 men at 200lbs per man? (160lbs per man + 40lbs equipment?) 

1.1 tons in anybodies measurement system isn't a lot for 10-12 men with equipment. It doesn't leave much for extras.

Edit> the weights given were for machines with the which in the front bumper, vehicles without the winch but with the roller were 500lbs lighter net, had 500lbs more payload and the same gross weight. 

US halftracks also carried 22 hand grenades and 24 anti-tank mines and fuses.


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## raumatibeach (May 11, 2012)

Interesting thread, I see Davebender compares costs between the US and Germany a fair bit.How much of the Germans manufacturing was done by slave labour?Maybe man-hours involved in construction is a better comparison?


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## Shortround6 (May 11, 2012)

The slave labor doesn't become a factor until later in the war. 

The bigger problems in comparing costs from country to country is that accounting practices weren't always the same(make sure contract being considered doesn't include either spare parts supplied to government or government is supplying parts like engines to the factory). and the fact that the currency exchange rate was pegged at a rather unrealistic level. It was not allowed to "float" in the open market in the last few years leading to the war.


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## barney (May 12, 2012)

Uncle Rex, now deceased, was a rancher. At any opportunity I would go there as a young man and stay at the ranch. Anyway, one of his sons was a truck driver and one day I was invited along for a run. 

We meant up with two other semi rigs and drove a long way on public roads. Then we drove a long way on private property crossing several cattle gates in the process. Finally we reached the cattle chute and all three trucks were loaded with cattle. 

The the talk amongst the drivers reveled they thought they might be in some trouble. It had rained the night before and the trucks had to ascend a hill right out from where they loaded. The first two trucks made a run at the hill and made it but my cousin and I didn't. The road, if you want to call it that, was by now just too torn up. So there we were stuck a third of the way up the hill. 

All of a sudden this M3 half track appeared driven by one of the hands. It still had armor plate on the cab but the box in back was missing. This was chained to our truck. I thought the thing looked too small to have much chance of pulling us up the hill but it didn't have any trouble at all.

So, as to how capable the M3 was, this one seemed capable indeed.


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## psteel (May 12, 2012)

The French Lorraine load carrier was essentially the basis of an APC. I recall there were discussions to make APC out of them. Germans captured about 400-500 and used them as Self propelled gun vehicles and command vehicles. When the issue of mobile infantry for the Germans emerged the contract came down to three designs; one an all terrain wheeled vehicle another the SPW we know and a fully tracked version with SPW body. The first model was dismissed and it came down to the last two proposals of which the army wanted the fully tracked version , but this was rejected due to insufficent tracked vehicle production. So in the end they settled on the inbetween model.


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## Dcazz7606 (May 16, 2012)

I've seen a photo of a converted M-10 used to move the 155 Long Tom and 8" artillery mover. This was acomplished by moving the aero engine forward just behind driver leaving the whole rear of the vehicle free for extra cargo, ammo etc... I don't see why it couldn't be converted with a rear door system like the amphibs.


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## tomo pauk (May 16, 2012)

Just take a look at the back side of the M 12 GMC - the engine was relocated into a middle part of the hull, leaving more space for the hefty cannon crew. Don't install the cannon, install the simple ramp instead of the earth spade, a roof and there you go. I've also proposed a while ago the similar conversion of the M3/M5 light tanks (with or without elongating the hull).


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## stug3 (Jan 6, 2013)

Universal carriers of the 1st Royal Gloucestershire Hussars on exercise near Guildford, 23 July 1940. One of the carriers is equipped with an experimental armoured roof.







A flamethrower mounted in a Universal carrier in action during a demonstration of flame weapons in Scotland, March 1942.






Universal carriers and infantry of 10th Battalion, Royal Berkshire Regiment advance ‘under fire’ during training near Sudbury in Suffolk, 10 June 1942.






Universal carrier of 53rd Anti-Tank Regiment being ferried across a river near Tanfield in Yorkshire using assault boats and pontoons by men of 16th Field Squadron, Royal Engineers, 10 June 1942.


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## michaelmaltby (Jan 6, 2013)

De-frocked Priest - or Kangaroo:


Used by the Commonwealth in Europe - post Normandy:

Kangaroo (armoured personnel carrier) - Wikipedia, the free encyclopedia


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## vinnye (Jan 6, 2013)

As Graugesit mentioned earlier, the USMC had the LVT - which although designed as an amphibious support vehicle soon became used to ferry troops to the beach.
Particularly after the Tarawa landings when the Higgins boats usually used could not cross the reef and made the troops wade ashore under fire and loaded down.
From Wiki -
The LVT 1 could carry 18 fully equipped men or 4,500 pounds (2,041 kg) of cargo.[1] Originally intended to carry replenishments from ships ashore, they lacked armor protection and their tracks and suspension were unreliable when used on hard terrain. However, the Marines soon recognized the potential of the LVT as an assault vehicle. Armored versions were introduced as well as fire support versions, dubbed Amtanks, which were fitted with turrets from Stuart series light tanks (LVT(A)-1) and Howitzer Motor Carriage M8s (LVT(A)-4). Among other upgrades were a new powerpack, also borrowed from the Stuarts, and a torsilastic suspension which significantly improved performance on land.

As a result of Tarawa experience, standardized armor kits were provided for the LVTs employed in contested landings, and the gun-armed "amtanks" LVT(A)-1 and LVT(A)-4 were developed to provide fire support. Armed with a 75 mm howitzer, the latter was especially effective in this role as it was capable of destroying Japanese fortifications as it came ashore. However the LVT(A)-4 had an open-topped turret which left the crew vulnerable to artillery and infantry attack, especially to the latter as it lacked any sort of machine gun armament. The lack of machine gun armament was eventually rectified, though the open-topped turret remained. Although usually used during landings only, in the Marianas campaign "amtanks" were employed inland, much like regular tanks.

The largest use of the LVTs was in the Leyte landing, with nine amtrac and two amtank battalions deployed. As there was no fighting on the beaches, this is also one of the least famous LVTs operations. Over 1000 LVTs took part in the Battle of Okinawa.

So, with regard to the original post, fully tracked troop carriers were thought of and used during WWII.


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## stug3 (Apr 27, 2013)

Scots Guards seen here on parade at the Royal Wanstead School, London, 9 October 1942.


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## redcoat (Apr 27, 2013)

stug3 said:


> A flamethrower mounted in a Universal carrier in action during a demonstration of flame weapons in Scotland, March 1942.
> 
> 
> 
> ...


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## vikingBerserker (Apr 27, 2013)

I would love to own a Bren Carrier


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## razor1uk (Apr 28, 2013)

Brilliant thread, loved the funny line


davparlr said:


> ...Of course I don’t really know if those are English kgs or American kgs. ...



Semi-off topic..
Yep we have had a funked up wieghts measures sytem, nowerdays we mostly use metric (Kg's) system (since the mid/late 1970's) which itself is identicle across all the Countries of the World over; although for roads, bridges and axle weights we still use the UK/Imperial with Metric as the secondary measurement (for international drivers). 
We still use MPH, and all UK speedometers are dual marked in KMH too - perhaps one of the only countries using dual marked sytems road signage. I was schooled from the 80's and have never officially been taught about lbs, oz, ton(s) and tons, let alone quater half-wieghts, shillings, guineas, farenhieght etc, and all that jazz - but a pint is always sacrosant, unless we eventually upsize to a litre glass standard.
Generally here we are semi bilingual in Metric and Imperial, and have found the US's slightly different Imperial system annoying, then again from their side, ours is/was just as much too them.

But in WW2, 'Imperial' wieghts measures still was 'top dog' for us (the UK,) Common Wealth/British Empire back then.


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## yulzari (Apr 28, 2013)

Imperial? What problems? A Guinea is 1008 Farthings with 21 shillings to the Guinea so it is obvious that a Pound is 96 Groats at 48 Farthings to the Shilling. I don't know why you young people think it was a problem. After all 5 Florins equals 2 Crowns.

If you have £17/11/6 1/4d and divide it by £2/7/4 1/2d how much is left over?


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## Ascent (Apr 29, 2013)

The Universal/Bren/Scout carrier shouldn't really be thought of as an APC but as an armoured Jeep. It was basically used in the same roles.

Also the Germans did develop a fully tracked APC at the end of the war based on the Sd.Ffz 138/2 Hetzer. It was called the Vollkettenaufklarer 38(t) Kätzchen and (according to Wikipedia) two prototypes were made.


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## stug3 (May 10, 2013)

This doesnt look very practical.


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## Shortround6 (May 10, 2013)

Try googling " machine gun bicycles " images and see what you get


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## stug3 (May 10, 2013)

Shortround6 said:


> Try googling " machine gun bicycles " images and see what you get



I bet a squad of these vs. a squad of mg wagons would be a very interesting spectacle.


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## Ascent (May 10, 2013)

I'm sure that there was one country that developed a motorbike with an anti-tank rifle and armour. The idea was that you would stop the bike and take cover behind it and use the rifle. Very unstable I believe.

I'm sure I've seen pictures but can't remember where.


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## MacArther (May 12, 2013)

I might be wrong, but didn't the Japanese have a full tracked APC either in production for China/Burma operations or nearing production near the end?


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## vinnye (May 13, 2013)

From Wiki -
The Type 1 Ho-Ki had an unusual silhouette, in that the driver's cab did not reach across the front of the hull, but stopped short about mid-way across the center line. Only one driver was required (although two were typically employed), who manipulated the left and right movement of the tracks via a pair of tiny steering wheels. Transport capacity was about thirteen men, and the maximum armor thickness was 6 mm.[3]

As the Type 1 Ho-Ki had been designed to pull artillery as well as to carry infantry, it had no rear exit hatch, it was felt that the towed weapon might interfere with the rapid exit of any onboard riflemen. Entry and exit of troops was thus accomplished from the left (driver's) side via three doors mounted side by side.[1]

The engine, which was located at the right front of the body, was a 6-cylinder, in-line, valve-in-head, air-cooled diesel.[4]

The Type 1 Ho-Ki was not normally armed, but provision was made to mount a machine gun to the rear of the driver. The Type 92 Heavy Machine Gun carried by Japanese infantry squads could be mounted in this position. Although it was an APC, it was often called a halftrack.


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## stug3 (May 13, 2013)




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## vinnye (May 13, 2013)

Thanks for the photos / drawings Stug3. The Wiki article did not have any - well done.


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## stug3 (Jul 10, 2013)

A British Universal Carrier Mk I comes ashore during the invasion of Sicily on 10 July 1943.


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## stug3 (Aug 26, 2013)

From Retronaut
Tiznaos, improvised armoured cars of the Spanish civil war

Some of these dont look very practical.


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## stug3 (Aug 30, 2013)

Rommel in his command vehicle with Panzer General Fritz Bayerlein, 1942


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## oldcrowcv63 (Sep 6, 2013)

The circa ~1937 jungle busting APC cruiser from _Tim Tyler's Luck_ serial (later seen on early TV)

Notcie the sloped frontal armor proving that Hollywood was far advanced over german armored theorists.


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## Denniss (Sep 7, 2013)

German armored cars like the 6-wheel Sd. Kfz. 231 always had sloped/angled armor. Something the tank designers did not understand or didn't see as necessary.


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