if you’re talking about the suggestion that the germans simply copy the t-34 straightaway, you could imagine the reaction of the german tank designers. not merely their natural pride in their own creations but also the fact that certain alloy components weren’t available to fully copy the russian tank.
Hate to break it to you, but the Panther was basically a result of that exact suggestion: a medium tank with excellent terrain capabilities and sloping armor.
Kombatminipig is pretty right- the Panther was a pretty close copy but better machined and finished. As has been suggested they did have teething problems and a lot of the early versions broke down- I understood this was corrected.
Many posts above, I read about slave labour and how there was sabotage and a huge number broke down due to this. I have yet to find any reliable evidence that any vehicle (or whatever) broke down due to slave labour sabotage. I am prepared to be corrected but I can’t for the life of me understand how a slave labourer could sabotage a machine so it could break down exactly on a battlefield rather than trials.
Also above, there was referral to the History Channels ranking of tanks etc. I would attach as much credence to that as the Flat Earth Society.
we’re talking about copying the t-34 straightaway (maybe under wartime conditions.) my basic cite would be “panzer leader” by heinz guderian. other sources will tell you it would have been impossible to copy the t-34 exactly. otherwise, all glory to the panther. :rolleyes:
Well, if F=MV^2, then solving for V yields V= square root of F/M, and F is no longer the Force applied to the target, but is now the Force applied to the projectile at firing (really, just a POV change).
The force/mass ratio is dynamic; one or the other can be “bumped” through technological means and techniques. For instance, advances in propellant charges can yield more F for the same mass of propellant; lengthening the barrel slightly may do the same, if there isn’t some “break even” (point-of-diminishing-returns) between barrel/projectile friction.
Tank projectile designers may decide that since they’re getting a “bump” from an increase in F due to better propellant, then they might also, for reasons dealing with the see-saw of competing advances in armor/anti armor technologies, bump M as well.
Yes. 
Just to make sure we’re speaking the same language, KE is how hard the projectile hits the enemy tank; momentum (conservation of) is the tendency of the projectile to continue to apply that KE to the target and bore through its armor.
As opposed to deflecting (due to some factor in the shape/size/mass/composition of the projectile), which is turning the whole mess on its ear and dealing with vectors, which happens anyway unless a projectile strikes at a perfect 90 degree with repsect to the target. Or just shattering entirely.
As mac points out, you’re now dealing with additional factors like the density, hardness, even thermal properties of the projectile, as well. Advanced metallurgy is not my thing, but I grasp the concept at its core.
You are correct in your boot/high heel analogy; you want to put the maximum force on as small an area as possible. You also want that force to “carry through” (conserve momentum) for as long as possible. Air resistance is a generally function of surface area, with other factors like streamlining and surface-effect coming into play. You might be interested to know that the M829A1 did not have a smooth surface; it was slightly ridged, as if it were wrapped in very fine wire.
Our unit Master Gunner mumbled something about a “bubble of air” around the projectile during flight caused by the little (tiny, really) ridges, overall reducing air friction compared to a smooth-machined projectile of equivalent size/mass/shape.
Whether that’s true or not you’d have to take up with an Army Master Gunner; the last one I knew I lost contact with almost two decades ago.
So yes, upping velocity will increase air resistance. Will that increase in air resistance offset the increase in velocity? At some point in the projectile’s flight to target, yes. Experts (Top. Men!) have probably crunched the numbers to ensure that the typical/effective engagement ranges are within (on the good side from the POV of the firing tank) that loss curve.
I would run it through a wind-tunnel for you, but I forgot to pack mine during my last move.
Mac: sorry if I came across as snarky last night. I was just trying to say that bigger (heavier) is not always the solution; and, you weren’t really saying that it was.
Advances in propellant, advances in projectile metallurgy and shape, can also yield improved penetration of the target’s armor.
Lacking those, though, the best options are either engaging at closer ranges (which The Enemy, that dastardly bastard, may not sit still for), or going with a bigger gun.
Missed edit window.
:smack: Change the above to say, “Advances in propellant charges can yield more F, for an increase in velocity for the same M(ass) of projectile.”
HEAT rounds don’t melt through anything. They penetrate armor, concrete, earthen barricades the same way an armor piercing projectile would - high pressure over a small area. A shaped charge produces millions of ATMs pressure/shock wave on an extremely small area. The shaped charge jet and pressure wave cause the target material to flow “plastically” away from the point of impact. There is a lot of heat generated by the armor being forced to the sides giving the impression there was burning or melting involved but it’s not the case. A shape charge warhead from a TOW2A will penetrate more than three feet of armor in miliseconds. You could sit there with a torch all day (pick your choice of torch) and not get through the armor. Wiki actually has a good summary of how a shaped charge works.
Since ammo has been my business for more than thirty years; a couple of other comments. More speed for the projectile? Add propellant volume, or increase speed of reaction, or use more energetic propellant, or add barrel length, or add barrel diameter (bigger piston) - or any combination of above. Drawbacks are weight of round, gun tube wear, weight of barrel/recoil/transport mechanisms, reliability/safety for the gun crew. How do you minimize velocity loss after leaving the muzzle? Small diameter/long length. As the M829 has evolved, the penetrator has increased in length but not diameter. Better metalurgy and manufacturing skill. Have a ablative coating and surface design to promote a smooth boundary layer. Add rocket assist. Add a fumer/tracer to the aft end of the penetrator to reduce drag.
We’ve (US) have looked at 140mm designs, maybe someday. Maybe a railgun. Heck, maybe a laser in the future. Right now, no pressing need for the next bigger thing.
QFT
The panther copied the good concepts embodied in the T-34 (heavy sloped armor, powerful AP gun, wide threads, forward mounted turret) but was a quite different vehicle: gasoline-engine rather than diesel, double torsion-bar suspension rather than Christie, welded armor rather than cast, turret crew of 3 rather than 2 (T-34/85 got a roomier turret as a response to the panther).
It was also heavier and more complicated. I have heard that the straight copy of the T-34 was rejected because german tank-industry would have problems producing a suitable diesel-engine and cast hull and turret.
I have read that the Germans were having great difficulties (by 1943) in making enough steel. This was basically because they had trouble producing enough coal-coal was used to:
-produce electricity to run factories
-heat homes and buildings
-make synthetic gasoline (a hugely inefficient process)
-make steel
The Germans had a big dilemma-coal diverted to steel production (to make more 58 ton Tiger tanks) took away from aviation fuel production (and the Luftwaffe needit fuel to fight off Allied bombers).
So would the Germans have been better off making smaller (Sherman) like tanks?
Increase speed of reaction: Quicker burning propellant will increase barrel pressure, right? It there an upper range to barrel pressure where even thickening the barrel will have difficulty making up for the increase in pressure?
Is the ability of the barrel to safely resist the pressure the limiting factor or is it wear and tear? I presume wear and tear is more of a factor in rifled barrels.
It’s not a debate, you are simply wrong.
and your authority for saying that is… your fellow cite-brains.
My username is my cite? That’s a new one.
Don’t worry, I believe you 
but according to me, he’s wrong. 
This is all true, but you say it like the Germans were not producing medium and light tanks in great numbers, specifically their marks 4 and Panther, which fulfill the same kind of role in the battlefield as Sherman. Read the thread, it is informative
as a field commander, guderian appreciated tanks for their various applications. one of his worse days was when they stopped constuction of the light panzer III which has proven itself to be very useful in fighting infantry and fast and maneauverable enough to evade heavier tanks. he considered heavy tanks not completely useless but not enough to make a signifcant impact (generals like more tanks.)
the recommendation that the t-34 be copied to exact detail was made by the tank commanders, not porche.
i can’t provide a cite but in most cases, german armor plating was welded sheet-by-sheet in a build-up process that took a lot of time. the russians saw the advantage of casting entire components, and machining them to sloppy tolerances for greater reliability. t-34s were as rough as cobs, according to american tankers.
If the external surface of the armor was rough, that part wasn’t “machined.” The machined parts of the turret and other parts would have been smooth. That’s not especially unusual - lots of things are cast, and then certain surfaces are machined to tight dimensional specs while other surfaces are left with a rough finish.
The T-34’s tolerances on moving parts couldn’t have been that sloppy or else they wouldn’t have worked.
The reason the Soviets cast things and the Germans did not has less to do with sloppiness or fussiness and, really, is probably attributable simply to design philosophy. The Soviets just did not believe in having a lot of different models of tank, or for that matter anything else, and rather than fussing over a lot of incredemental improvements, preferred to implement many improvements all at once so that production wouldn’t be interrupted. That philosophy makes it easier to build your tank with cast parts, because you can keep using the same molds.
sorry, when i say “sloppy tolerances,” i didn’t mean parts that simply won’t fit or mesh. i meant tolerances in the context of inter-parts “play” that allows for easier assembly/re-assembly/repair without sacrificing relibility. the best analogy i can mention is the 1911 colt .45. notice how the slide rattles with the barrel? that amount of play is intentional. it makes for a reliable action but bad for accuracy. the first thing frank pachmayr did in modfying a .45 for target was to install a “slide tightener.”