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Its almost impossible to keep up with this board and have a full time job/life.

I havent read all the posts but I want people to give thought to the following:

The resolution of the elevation machanism has as much impact on the gun/sight system accuracy than anything else.

Without the ability to make fine adjustments to the super elevation can almost assure inaccuracy. Long range shooting depends on it even with a high velocity gun.

For those that are engineers or care; repeatability in the mechanism and the absense of backlash are important also. I would highly doubt hydraulics are used for this but much rather gearboxes (and all the foibles that go with them).

But I am sure people here can supply gear ratios and backlash specs on all the weapons..

Lewis

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I may be a bit confused but surely after a certain number of rounds the effect of bracketing (in real life) should plateau as rexford suggests, I would certainly be suprised if the relationship was linear as Duke seems to assume. I am not entirely sure as to how rexford has arrived at these 'to hit' figures but the trend seems clear if not the absolute values. Furthermore considering the gun dispersion in isolation of other sources of dispersion and error gives a somewhat skewed impression of what might actually occur. Since Lewis seems to have posted along the same lines as myself I generally concurr with his points. ie the analysis here seems fairly simplistic biggrin.gif

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Muddying the waters as usual.

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rexford,

thanks for your chart. No offence, but I still think those numbers are way too conservative for the 88L71, especially for Elite gunners.

Those numbers, though probably numerically accurate, do not coincide with what the Nashorn was routinely able to do to the Russians. There is something that is missing from your estimates, I do not profess to know what that is, but even 48% after 8 rounds is just not right.

See, what you are saying is that less than HALF the time, even after firing 8 rounds at a stationary target, the Nashorn with a crew that had been there from the start...knows this weapon system like the back of their hands...is simply intimate with it...and have probably killed at least 5 to 10 enemy AFV's, still cannot hit its target? Just doesn't fit. No matter how much your calculator tells you that this is the most they could do...it's just not right.

Jeff...do you have any other accounts of the Nashorn in action?

I still EAGERLY await BTS's input on this...please guys, we could really use you here. We are on to something that could potentially "fix" med to long range gunnery but need your expert advice.

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One shot...One Kill

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<BLOCKQUOTE>quote:</font><HR>Originally posted by Iron Duke:

rexford,

thanks for your chart. No offence, but I still think those numbers are way too conservative for the 88L71, especially for Elite gunners.

Those numbers, though probably numerically accurate, do not coincide with what the Nashorn was routinely able to do to the Russians. There is something that is missing from your estimates, I do not profess to know what that is, but even 48% after 8 rounds is just not right.

See, what you are saying is that less than HALF the time, even after firing 8 rounds at a stationary target, the Nashorn with a crew that had been there from the start...knows this weapon system like the back of their hands...is simply intimate with it...and have probably killed at least 5 to 10 enemy AFV's, still cannot hit its target? Just doesn't fit. No matter how much your calculator tells you that this is the most they could do...it's just not right.

<HR></BLOCKQUOTE>

Why? What actual evidence do you have that Nashorns could get the hit rate you claim they had at those ranges?

I am not really sure how you became so covninced that hitting vehicles at 3 kilometers with WW2 sites was this easy, regardless of the experience level of the crew.

You do realize that 3kM is considered an extremely long ranged shot TODAY, with laser range finders and much, much more accurate ammunition?

Jeff Heidman

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Jeff,

actually I don't have any "proof" that they did better. But that will change. And please remember that I am saying this based on the stationary Elite Nashorn firing 8 rounds at a stationary AFV.

BTW: 3000 meters is a long shot, but one easily made...at least by the M1A1. Even on the move AND the target moving. wink.gif

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One shot...One Kill

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<BLOCKQUOTE>quote:</font><HR>Andrew Said:

In many cases -- as I and others have pointed out in other discussions -- it may be the case that the gunners already had a pretty good idea what the range was due to a number of factors. For example, I'm struck in many accounts of long-range accuracy how frequently there was a noticeable feature near where the attack occurred.<HR></BLOCKQUOTE>

Agree. This is yet another not quite so obvious advantage of a prepared defensive position. Vehicle or gun crews would prepare range cards. Any prominent terrain features, as well as anticipated avenues of advance, would be ranged in by ATG’s or tanks sitting in a defensive mode. It was probably very nice to have an Em or SF type range finder during those moments of range card prep.

Examples of German tank crews employing scissors or Em range finders:

http://www.battlefront.com/discuss/Forum1/HTML/013902.html

=================================

Regarding Rexford’s accuracy numbers for 3000 meter shots, they don’t look conservative relative to readily available published data. I also know from studying some of Rexford's earlier posts that his group has access to less readily available German test data for various main-guns.

Since we have yet to bring a Jentz reference into this thread, here are his tired old numbers for 88L71 (pzgr 39/43). 2x3 meter sized target…stationary.

Range......Hit Probability

...2000m.................(43%)

...2500m.................(30%)

...3000m.................(23%)

Jentz indicates that these numbers represent realistic combat accuracy achievable by “cool-gunners” after the second round (i.e. at least one bracketing round had been fired). I'm more inclined to buy into Rexford's numbers than the Jentz numbers, simply because bracketing advantage will tend to boost hit probability even after the 2nd round. I also agree that bracketing benifits probably have a plateau.

I have also seen German WWII Gunnery manual excerpts indicating that firing on moving targets beyond 2000 meters was forbidden. German gunnery training for tank sized, stationary targets at ranges from 1200 to 2000 meters was at least 1 hit in four rounds allotted for the exercise.

The problem with ranges extending out to even 2500meters is that targets begin to look like little specks in the gunner’s sight. The thickness of a stadia line in the gunner’s site overlaying a target at this range represents a big chunk of the visible targets size. Magnification on the TZF9b&c is 2.5X or 5.0X. Many modern MBT's are using 10x or 12x magnification optics in both GPS and GAS.

Optical magnification advantages in gunnery was discussed at length by Conell on the 88 Accuracy Thread. Good stuff. A 3000 meter shot is considered good even by modern standards, although I can dig out 2 dozen or so AAR’s detailing 2500 to 3000 meters shots during WWII.

I think what is exceedingly crucial to any discussion on accuracy is crew training and crew experience. There is really a huge difference between green crews with little training, and green crews with good training.

[This message has been edited by Jeff Duquette (edited 01-17-2001).]

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Thanks to all for the information.

I concede that a 3000 meter shot for WWII was a very long shot, and to tell the truth, I would happily take rexfords chart to the current 10% that is seen in the game.

Now if we could just get BTS to chime in...

OT (kind of)

Of the 152 AFV's and misc vehicles my battalion destroyed in the Gulf, a good 80% of the shots were all over 2700meters and quite a few over 3000. There was one in particular that was witnessed by the battalion commander himself, a Lt. Col Meritt. It was a shot on a BMP while on the move with a HEAT round, the range was 3980meters and was made by 3rd tank, 3rd platoon, Delta company...my tank. At first Col. Meritt thought that we had fired a sabot round while indexed HEAT, but to his surprise, the tracer went waaay up into the air and then began to slowly fall back down only to land square on top of an offending Bemp. wink.gif Yeah, 3000 meter shots are long, but as the saying goes: "if you can see it, you can kill it".

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One shot...One Kill

[This message has been edited by Iron Duke (edited 01-17-2001).]

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This is from an old TRADOC Bulletine. 30, September 1975. Range and Lethality of US and Soviet Anti-Armor Weapons. I dont think this stuff is classified any longer wink.gif Anyway it demonstartes a couple things...including long range accuarcy, and the increased hit probability associated with aquisition.

TRADOC_1.jpg

As far as BTS chiming in...they have been. See pages 1, 2, and 3 of this thread. They're prolly busy making CM2.

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<BLOCKQUOTE>quote:</font><HR>Of the 152 AFV's and misc vehicles my battalion destroyed in the Gulf, a good 80% of the shots were all over 2700meters and quite a few over 3000.<HR></BLOCKQUOTE>

Yeah but now your talkin starship M1A1's wink.gif First round fly castration at 4000 meters with SABOT. I crawled around in an M1 once at Ft. Knox when I was in basic back in 1983 (ok so I really only got to stick my head into the drivers hatch wink.gif). It was just being phased in as I recall. The engine sound kinda reminded me of a jet taking off.

I trained on the M60A1 and my Guard unit was equipped with M48A5's. Cobra company killed a fair amount of plywood targets at Ft Irwin over the years wink.gif

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I have taken 35 minutes to read this post, by GOD, interesting stuff!

But this thread can be captured as follows:

Can CM or/and CM2 tank hit probability % be increased after every round fired at the same target, that is can we better incorporate the method of bracketing as it currently stands in CM1.1?

Is Charles planning to incorporate this in the very least with CM2?

Thanks all you guys for this awesome thread!

Charl Theron

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For those that still may have doubts about the numbers Rexford has been batting about, I have been studying the trajectory model Rexford was kind enough to present to this forum. Check the following thread for the nitty-gritty:

http://www.battlefront.com/discuss/Forum1/HTML/014368.html

(For ease of writing style assume when I say Rexford, it implies Rexford’s group…i.e. the “we”)

I laid out my own spread sheet to emulate the function Rexford presented in the above thread. I was curious how it stacked up against some actual data. As I only have access to an example of gunnery\accuracy\trajectory relative to range of the 88L56 (provided in the “Tigerfibel” I decided to give it a whirl). This is the example of which I speak.

tigerfibel3.jpg

Important Note: Bear in mind that the aim point in the TigerFibel example is Elvira’s toes.

From Rexford’s formula:

Driver Oscar’s range estimate of 475m plugged into the trajectory formula yields a hit location of –0.12 meters below the aim point (projectile flight time: 0.62s). So Rexfords numbers predict a near miss…round lands in front of Elvira’s feet. Compares well with Fibel.

Radioman Weenie range estimate of 500m plugged into the your trajectory formula yields a hit location of 0.0 meters…direct hit on aim point (projectile flight time: 0.65s). So again Rexford’s numbers result in the round hitting Elvira in the toes. Good match again between Fibel and your numbers.

Loader Barrelbum range estimate of 700m plugged into the your trajectory formula yields a hit location of 0.95m meters above the toes (projectile flight time: 0.93s). So Rexford’s numbers predict a hit in Elvira’s in mid-section. Again Rexford’s numbers compare well with the Fibel example.

TC Smart’s range estimate of 1100m plugged into the your trajectory formula yields a hit location of 2.85 meters above the toes (projectile flight time: 1.49s). So Rexford’s numbers predict another over-line shot. The TigerFibel also predicts an over-line shot over Elvira’s head.

Conclusion: Rexford knows his stuff on this topic.

[This message has been edited by Jeff Duquette (edited 01-17-2001).]

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I'm glad that we have determined that the Germans knew their kinematics (high school physics). The Tiger Feibel basically asserts that one needs to aim farther than the actual target because the target has a certain amount of height or one needs to aim at 500m distance and 1m elevation above the ground. Unfortunately the real question about hit probability is much more complicated since it relies on someone correctly estimating the range quickly under battlefield conditions. Not any of us sitting at home with our spread sheets and calculators figuring it out.

I don't claim to know from scholarly study, reading or first hand knowledge how well tankers were able to estimate ranges under battlefield conditions. How well and how often did they properly following bracketing procedures? There are also a lot of other physical factors that the simple kinematics does not consider such at uneven ground, wind, and dispersion. I think that people who want to increase the chance to hit need to research the psychological factors that affected the tank gunners. Then they should make their arguments from that standpoint, since that is what is hard to model properly. Not the solutions to projectile motion, which I believe that Charles has modeled properly in the game.

Theron

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Jeff D.

I completely agree that Rexford is the man on this subject. I will say it again...Rexford is the man. smile.gif

The only thing I want to emphasize is that, IMO the underlying physics already in the game are pretty good, BUT as is readily shown in-game, bracketing is not allowing for follow-on shots to kill targets without emptying your basic load.

I think with a combo of Rexfords tables and perhaps just a little tweaking of CM, we could see a vast improvement in the med to long range gunnery.

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One shot...One Kill

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<BLOCKQUOTE>quote:</font><HR>Originally posted by Andrew Hedges:

For example, I'm struck in many accounts of long-range accuracy how frequently there was a noticeable feature near where the attack occurred. <HR></BLOCKQUOTE>

I remember one account in particular involving the Free French recaputure of paris. One tank was Place de la Concorde, at one end of the Champs Elyesee(SP?), while the other hid around the Arch de Triumph. One french tanker remebered his grammar school 'monuments of paris' lesson, and dialed the range in at 800m. Result: one dead panzer.

I have one comment in general, regarding 8 hits per hit comment. That is an overall figure, representing many, many longer ranged, shoot and scoot, harrassing firefights. Just the types of battles which were very typical, but not simulated in CM. As I have said before, most battles fought in CM simulate a very small percentage of battles; the proverbial very sharp point of the stick. These battles are the few where determined attackers met determined defenders in relatively equal strenghts.

For example, one thing that I have noticed about historical scenarios, they tend to cover the same ground over and over. I.e., the early counterattacks around Caen involving the 12th SS, The first week or so of the Bulge, Hurtgen (SP?) forest, etc.

[one hour train of thought break as all hell breaks loose around me]

Why? Because there were damn few historical situations that make for fun, competitive scenarios.

And in these battles, I would suspect hit rates were alot higher, because playing hide and seek was not as much of an option. The infantry was advancing and needed armored support. Unlike in more typical situations, where the advance would be halted once serious resistance was found. And usually a few shots from a 75mm gun were enough to signify 'serious resistance.'

WWB

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Before battle, my digital soldiers turn to me and say,

Ave, Caesar! Morituri te salutamus.

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<BLOCKQUOTE>quote:</font><HR>Originally posted by Iron Duke:

OT (kind of)

Of the 152 AFV's and misc vehicles my battalion destroyed in the Gulf, a good 80% of the shots were all over 2700meters and quite a few over 3000. There was one in particular that was witnessed by the battalion commander himself, a Lt. Col Meritt. It was a shot on a BMP while on the move with a HEAT round, the range was 3980meters and was made by 3rd tank, 3rd platoon, Delta company...my tank. At first Col. Meritt thought that we had fired a sabot round while indexed HEAT, but to his surprise, the tracer went waaay up into the air and then began to slowly fall back down only to land square on top of an offending Bemp. wink.gif Yeah, 3000 meter shots are long, but as the saying goes: "if you can see it, you can kill it".

<HR></BLOCKQUOTE>

Reportredly the 2 'confirmed' longest range Abrams kills in the Gulf; were 3,750m, & 3,250m. Both were on the move kills, these ranges have been sited in numerous books & mags etc. Did your BN not confirmn the 3980m kill?. The longest confirmed kill was made by an Challenger @ 5100m.

Regards, John Waters

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"We've got the finest tanks in the world. We just love to see the

German Royal Tiger come up on the field".

Lt.Gen. George S. Patton, Jr. February 1945.

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John,

I guess not. The only conformation we had was that Col. Meritt came up to us and asked us about the shot. Later on when Brigadier General Black came around to each company, to our surprise, he had heard of Sgt. Turner's (my gunner) shot...apparently Col. Meritt had gone off braggin about it! smile.gif So as far as 'confirming' it...I don't know.

The two shots that you say were confirmed...do those happen to be from the "Tiger Brigade" during the battle of 73 Easting?

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One shot...One Kill

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<BLOCKQUOTE>quote:</font><HR>Originally posted by Iron Duke:

The two shots that you say were confirmed...do those happen to be from the "Tiger Brigade" during the battle of 73 Easting? <HR></BLOCKQUOTE>

Darn I have heard reports of longer ranged kills for the Abrams then the 'confirmed' ones. Their was also an 'unconfirmed' from a Challenger to, that was reportedly at 7,200m on a fuel browser; from a crewmans posts. Anyway yes, both the 'confirmed' were during Easting.

Regards, John Waters

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"We've got the finest tanks in the world. We just love to see the

German Royal Tiger come up on the field".

Lt.Gen. George S. Patton, Jr. February 1945.

[This message has been edited by PzKpfw 1 (edited 01-17-2001).]

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That doesn't surprise me, as that battle, being the most "textbook", where 1 Cavalry Bde surprised and destroyed a much larger force, has basically gotten all the press!!! mad.gif

There are numerous stories untold from MANY different units throughout 3rd Armored and 2nd Armored that no one has heard, only because no one has bothered to write about.

Take this one:

I know that on websites and in books you can find the 'exact' numbers of US troops killed but they are wrong. Period.

During the 3rd night of the ground war, a whole platoon of M1A1's where stamped off the face of the earth by what appeared to be either F-16's or A-10's, those two being the most frequent flyers in our sector. There is only one weapon system that will do what we saw to an M1A1...and that is a Maverick ATGM, with its 150+ pound warhead, it really smashes a tank. Even the mighty M1A1. The whole plate that acts as a roof for the drivers compartment is violently smashed inward to meet the hull floor plate. The 23.1 ton turret it thrown off the tank like a bottle cap and the suspension system completely melts down into slag. The only thing we could find of those poor bastards where pieces of their Kevlar helmets and, surprisingly enough, portions of their pay slips (I have forgotten what those damn things are called). My company commander, Capt. Rodriguez kept a burnt up .50 cal barrel from one of the M1's as a rememberance for those men. It was a sobering day to say the least. Anyway...even though you may have never of heard of something that happened over there doesn't mean it didn't go down that way. wink.gif

BTW: The same day that Bde. General Black visited our Company and asked us about that shot, WE confronted him about what we had found (the 4 tanks), we had him by the balls at that moment and he admitted to us what had happened. So even US troops where kept from this information and I don't really think anyone knows the exact KIA figure. Ask DEF BUNGIS about what he knows about it...he was in my Battalion also, but in Charlie company. He might have something to add here.

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One shot...One Kill

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<BLOCKQUOTE>quote:</font><HR>Theron Said:

I'm glad that we have determined that the Germans knew their kinematics (high school physics). The Tiger Feibel basically asserts that one needs to aim farther than the actual target because the target has a certain amount of height or one needs to aim at 500m distances and 1m elevations above the ground. Unfortunately the real question about hit probability is much more complicated since it relies on someone correctly estimating the range quickly under battlefield conditions. Not any of us sitting at home with our spread sheets and calculators figuring it out.<HR></BLOCKQUOTE>

Sorry Theron, I had figured from your previous posts supporting Charles flawed logic on what is really occurring in tank gunnery that maybe a simple example was required. If you read through this thread there is a fair amount of confusion by folks on where Rexford is coming up with his numbers. His equations are determined from regression equations through numerous data points for every German gun listing. Correlation R squared is typically over 0.99. Regression was based upon actual trajectory information. You can plug and chug through your high school kinematics equations till your blue in the face and you wont match actual trajectory paths.

Regarding range estimation this is a function of training, training and more training. German, British, and US ARMY WWII training manuals for tank gunnery stress drilling in range estimation via several methods. So it was something that was taken very seriously by all major belligerents. Most military binoculars issued during the war had stadia lines for range estimation via a mil relationship. In addition, all German assault guns were equipped with scissors type range finders. There is also fair amount of evidence suggesting that Tiger, Panther and MkIV crews were also using SF14z range finders. The intent of the last 30 posts was to show why error in range estimation doesn't, in and of itself, mean a gunner will miss his target. Look at the Fibel example again, and it should become apparent to you that for the 88L56 range estimates of between 500 to 1000 meters against a 2meter high target located 500 meters from the firer will still result in a hit. This is fundamental.

In addition, many opponents of the Tiger were in fact taller than 2meter. The T34 was something like 2.4 meters…Sherman was what?…2.75meters in height. This only acts to increase the size of the range estimation error envelope, which would still result in a hit.

Using your high school kinematics equations describe the range estimation envelope which will still result in a hit on a stationary Sherman tank by a Tiger firing APCBC. Assume the Sherman is 700 meters distance from the Tiger. Assume the Tigers aim point is the Sherman's center of mass. To ease calc's you can assume no lateral or vertical round dispersion from aim point.

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<BLOCKQUOTE>quote:</font><HR>Iron Duke Said:

I completely agree that Rexford is the man on this subject. I will say it again...Rexford is the man.<HR></BLOCKQUOTE>

Sorry Duke. I wasn't trying to beat a dead horse with you. I was simply enthused about the match between Rex's stuff and the Fibel example. I read through the fratricide info. Very bad luck for those tank crews.

Question: I haven't been much of a student of the Gulf War. Were there any cases of the M1's armor being penetrated by Iraq Tank rounds?

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None that I know of. In fact, one of the lessons we learned out there is that WE cant penetrate our own tanks!!

Apparently, as the story goes, there was an M1 that became so badly bogged in very soft sand that it was decided to blow it in place and continue on with the mission. They had another M1 come along and shoot a sabot round at it...ping! Off the front armor...another round..ping!!! off the SIDE armor...(must have been lucky there), finally they shot it through the rear but the Halon system in the tank put the fire out before it could do any real damage. biggrin.gif

So they had to wait until a few more M-88's showed up from other outfits and finally pulled the damn thing out. Hehe. I don't know how tall that tale is but it was one that went around the unit. wink.gif

If I remember correctly only 2 of the 52 tanks in my Battalion where even hit with Iraqi main gun rounds and they were both ricochets. Front armor I believe.

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One shot...One Kill

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Duke:

A couple questions if you have the time.

How much time does the ARMY spend in training you guys in targeting with auxiliary gunners sight now days? How confident do you feel your men or you are in battlesight gunnery? No LRF’s for range estimation just GAS. Can you hit something at 2000m with confidence using only GAS.

This is perhaps a tad bit personal, but I think relevant to the original intent of this thread. How did your “adrenalin flux” during combat affect your ability to perform the job you were trained to do? I dunno if you were a gunner, loader, TC, platoon commander or what…but what ever your function was how did this effect your ability to perform your job? Did you feel like there were a lot of gaps in your training…was there things that should have been taught or considered during one of your rotations at NTC or the like?

Same question except based upon your observations of other folks in your unit?

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<BLOCKQUOTE>quote:</font><HR>Originally posted by Iron Duke:

Apparently, as the story goes, there was an M1 that became so badly bogged in very soft sand that it was decided to blow it in place and continue on with the mission. They had another M1 come along and shoot a sabot round at it...ping! Off the front armor...another round..ping!!! off the SIDE armor...(must have been lucky there), finally they shot it through the rear but the Halon system in the tank put the fire out before it could do any real damage. biggrin.gif

So they had to wait until a few more M-88's showed up from other outfits and finally pulled the damn thing out. Hehe. I don't know how tall that tale is but it was one that went around the unit. wink.gif

<HR></BLOCKQUOTE>

Ahh the imfamous Clancy version. IIRC this was debunked a while back. Their is a report on cause of loss on US units from the Gulf I had it saved till my HD crash. Paul if your lurking could you post it?.

IIRC of the 4 Abrams that were hit during Ie, Easting, their was controversey over what caused the damage, originaly it was thought to be friendly fire from Apache's that were operating in the area, but examinations found 125mm HEAT damage, as well as 1, 125mm APFSDS impact.

But anyway thats just from reports released after as Duke related other things occured that we prolly still haven't heard about.

On a similar note, spaced plates were welded over the front hull armor of the earlier M1's, as their was an real concern that 125mm HE/Frag rounds with repeated hits, would open up the outer armor & expose the inner layers hence the urgency of getting the M1A1HA's to the Gulf.

Regards, John Waters

------------------

"We've got the finest tanks in the world. We just love to see the

German Royal Tiger come up on the field".

Lt.Gen. George S. Patton, Jr. February 1945.

[This message has been edited by PzKpfw 1 (edited 01-17-2001).]

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