Long post, sorry but it just growed!!
Heya,
Just a few comments from a very recently retired Tanker in U.S. Army (LTC).
50 Cals DID kill tanks in WW2.
50 cals DID kill modern armor in Desert Storm. Not main battle tanks but the ammo was definitely capable of penetrating even frontal amror of APC's (armored personell carriers) as well as lighter armored or fortified structures.
50 cals WILL cause considerable damage to such heavy vehicles such as an M60 tank. Our main battle tank prior to the M1 series. A 50 cal will DESTROY the main gun on a tank if hit repeatedly. The main gun is obviously a hard steel but so is the penetrator in a 50 cal AP round.
Artillery in WW2 was a main killer of tanks and not by direct hits either. Many tanks of the time had external oil and fuel storage on the vehicle. If you penetrate them and set them afire the crew typically unasses the vehicle to avoid the fire and susequent ammo cook off.
Here is some info.
Most a/c tank kills in WW2 were not catasrophic kills but a mobility kill. One a tank is immobile it becomes a fixed object removing one of it's primary assets notably the shock and speed. A fixed emplacement can be killed MUCH easier than a mobile one hence the crews interest in getting away from a stuck tank. The tracks and wheels of armored vehicles even today are capable of being damaged / destroyed by a 50 cal.
Spatula, 50 Cals are not just lead. They are a mix of ammo. 50 cal ball is a lead core in a very thick copper jacket. AP ammo is a hardened steel core (penetrator) inside a copper jacket. The reason for the jacket is to seperate the steel from the barrel so that barrels don't wear out in a few rounds. The other types of ammo in a typical combat mix were, ball, armor piercing, incendiery, tracer, ap-incendiery. This ammo is designed with a pointed tip not just to maintain velocity but as an aid to penetration. Rounded projectiles are much more prone to ricochet than are pointed bullets. Pointed bullets dig the tip in and penetrate. That is why the main anti tank ammunition in a tank is a very sharply pointed depleted uranium non explosive solid shot penetrator. What the round doesnt destroy by direct penetration is destroys by spraying white hot molten metal in the vehicle. This molten metal was formerly the armor of the vehicle. Sometimes this material is referred to as spall.
Armor design in vehicles is predicated on the environment they are expected to face. They are also based on real world considerations. You can make armor that cannot be penetrated by weapons up to 120mm ap rounds but you will not be moving it on the battlefield. It will be so heavy it won't move period. Armor is set up to be thickest on the front slopes. A curve of the slope gives protection equivalent to much thicker armor due to the oblique angle through the armor a shot would have to take to fully penetrate. Rounded armor is typically a casting of homogeneous armor grade steel such as the M60 turret and hull. WW2 armor was usually a stack of stel plates welded, bolted or riveted together. This often had sharp angles. Welded is stronger than bolted but look at WW2 armor. There was a lot still bolted on to the base armor plate. It was an easy way to add additional armor protection to the vehicle but the weight aften slowed it down. Patton was known to critcise the placement of sand bags on Sherman tanks. He did this as it was a way to slow the tank down due to the weight. High speed was the main advantage American armor had over German armor at the time. If you slow the tank down it becomes easer to hit. There were no gyrostabilized guns with laser rangefinder at that time. The heaviest armor of the WW2 era was the German Ferdinand. It was a 72+ ton monster and could take hits from the Russian 85 mm guns on their main battle tank, at least until it became immobilized. The infantry then swarmed it firing into vision slits and using molotove coctails to fry it.
In order to make a tank move it takes power and a compromise of weight and protection.M48's and M60's got the designation as that is the approximent weight, in tons, of that class of vehicle. They were refered to as 60 class vehicles. The top and rear of a tank are it's most vulnerable spots for HULL penetration.
Armor thickmess of a M60 was only about an inch on top of the turret. This is a more modern vehicle with better steel than WW2 armor. The rear grills that the engine exhaust and heat is vented through is a grill. This is NOT a solid peice of steel but looks more like overlapping angle iron bars. They cover the engine AND fuel tanks on a 48 and 60 series tank. 50 Cals can get through this stuff if allowed a bit of time to put repeated hits on it. There are also grills, albeit smaller ones, on the top side edges of the engine compartment that allow air into the engine compartment. The engine is air cooled and requires a lot of air. These grills are very close to the fuel tanks which are also in the engine compartment. These grills are a compromise in weight, protection and design to alolow the tank to function. Yes it is a vulnerable point as ANY burning liquid going into this area will be likely to start a fire. Yes diesel burns less easily than gasoline. Diesel forms vapor at 65 degrees F and it is much hotter than that in that compartment. Where you have fuel vapors you have a potential for fire. Sparks and flamable materials like incendiery material from incediery amunition can light off the fuel in a deisel tank.
All of this stuff I am talking about is still current for today's armor vehicle. It was more of a concern in WW2 as materials and design had not matured as much as today. In short, tanks were killed in WW2 by 50's but not as easily as by 20mm's or 30mm's. If you hurt the vehicle and took it out of a battle due to damage so that the crew abandoned it, it was a "kill". It didn't have to be destroyed to be a battle loss. If you left it on the field and the enemy captured it you kinda lost it just as much as if it blew to fragments.
The fact that you can't kill a tank in AH by 50 cals is not an overmodeling of the tank as much as it is an under modeling of 50 cals. The 50 cal is a serious weapon and capable of destroying equipment much heavier than you would think.
Mav
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No Mercy Asked, None Given, Just pass the ammo
[This message has been edited by Maverick (edited 07-30-2000).]