Composite Armor For The M-60

[ShotMagnet]

According to what I've been reading, the M-60 was originally supposed to have been equipped with composite armor, but went into production without it.

 

Why?

 

 

 

 

Shot

[Walter_Sobchak]

According to Hunnicutt, "Originally, it was intended to provide siliceous cored armor on both the turret and hull. The T95E7 type turret and the flat square front of the glacis plate on the new hull casting simplified the application of siliceous cored armor. However, cost and the limited availability of production facilities resulted in the cancellation of this feature and all M60 series tanks were protected by conventional homogeneous steel armor." The T95E7 type turret was dropped from the design, replaced by a version of the existing m-48 turret.

 

if you really want to read more about it, you can download "Evaluation of Siliceous Cored Armor for the XM60 Tank"

[Loopycrank]

That said, they did ultimately plonk a T95-derived turret onto the M60 with the M60A3.

[Walter_Sobchak]

That said, they did ultimately plonk a T95-derived turret onto the M60 with the M60A3.

 

I suspect Loopycrank meant M60A1 and M60A3.

 

Here is a picture of the original turret design.

 

[rmgill]

Looks like a pretty compact and crowded turret.

[Mr King]

That said, they did ultimately plonk a T95-derived turret onto the M60 with the M60A3.

 

Did this one have composite armor?

[Walter_Sobchak]

 

That said, they did ultimately plonk a T95-derived turret onto the M60 with the M60A3.

 

Did this one have composite armor?

 

No, the turret on the M60A1 (same turret at the M60A3) was conventional steel. The first US tank to have composite armor was the M1 Abrams.

[Mr King]

 

 

That said, they did ultimately plonk a T95-derived turret onto the M60 with the M60A3.

 

Did this one have composite armor?

 

No, the turret on the M60A1 (same turret at the M60A3) was conventional steel. The first US tank to have composite armor was the M1 Abrams.

 

 

Thanks

[Ken Estes]

 

That said, they did ultimately plonk a T95-derived turret onto the M60 with the M60A3.

 

I suspect Loopycrank meant M60A1 and M60A3.

 

Here is a picture of the original turret design.

 

 

The T123E6 was the ultimate development of the 120mm tank cannon intended originally for the M103 heavy tank. The E6 version was made lighter by using 160K psi yield strength steel, formerly 100K psi, reducing weight to 4244lbs total vs the earlier 6280 lbs. At any rate, it was the favored gun nominated by Ord Dept for the XM60 project, but the army logistics staff rejected it, for its semifixed ammo. At the APG shootoff of Oct58, the T123E6 outperformed all candidates except in rate of fire, for which Ordnance had proposed an autoloader. But it was in the competition only as a base gun, and the British X15E6 105mm was chosen for the production M60 series.

 

Had the army installed the 120mm gun in the M60s, there would have been no NATO standard tank cannon in the 1960s, but there would have been no question of US tanks being undergunned vs those of the USSR. One has to wonder if the USSR went to the 125mm guns because of the US/UK fielding of the T123 series guns, for they probably knew of these developments. All this lends support to my notion that the M103 proved the progenitor of the modern 3d-4th gen MBTs, not the deadend M60.

 

Some day a history of the Tripartite Tank Committee ought to be written, for these questions of caliber and matches to the USSR must have come up regularly. David Fletcher told me that they have a complete set of the minutes at Bovington Museum Library, which would be far more convenient than NARA. It was the Fourth Tripartite Conference on Armor and Bridging held at Quebec, Canada during October 1957 that apparently was first to coin the term Main Battle Tank, something often asked on this forum.

 

 

 

 

 

[Loopycrank]

How would the M60 have dealt with the recoil? I seem to recall some descriptions of the M103 as a pretty wild ride when that M58 was touched off. Surely the several-tonnes lighter M60 armed with a T123E6 would have been even more exciting.

 

That T95 variant (E7?) with the 120 would have been pretty wild too.

 

Were there any plans to lengthen the stroke of the recoil cylinders or anything like that?

[Ken Estes]

Good point. Perhaps the solid shot AP would have been left out in favor of lighter APDS. Using the 51 lb AP, the tube life was only 150 rds and the muzzle energy more than double any 105mm round. Bore life shooting HE was 500 rds. Kind of endorses smoothbore guns for the future, I guess.

 

Maybe the test reports for the 1958 shootout at APG can be found.

[Loopycrank]

It occurs to me that stabilized optics might have helped the problem of follow up shots, assuming the stabilization was up to dealing with pitch rates that high.

[Ken Estes]

I don't believe that the Stab of the day could not keep up with suspension pitch on the move, so the rockback of the 120mm recoil on an M60 series tank would have been impossible to handle that way. Maybe the master gunners can tell us.

[Lionel Mandrake]

Anybody recall what was supposed to be the composition of the armor on the mid-60s Chrysler K-Turret with the 120mm Delta Gun that was proposed for use on M-60 hulls?

 

The only picture of it I have ever seen was in the old Squadron M-60 In Action book.

 

From the front, it looked quite a bit like the prototype M1 turret complete with that odd “pig snout” and all...

[BabyOlifant]

Did they ever mount that turret with the T123E6 (T96 turret?) to the M60?

 

What was the rationale for fielding the 105mm instead? What were the objections to semi-fixed ammunition?

Edited October 4, 2013 by BabyOlifant

[DKTanker]

Did they ever mount that turret with the T123E6 (T96 turret?) to the M60?

 

What was the rationale for fielding the 105mm instead? What were the objections to semi-fixed ammunition?

T123E6 4.8" @ 2000 meters 60d

105mmX20 4.7" @ 2000 meters 60d

 

For the additional 1/10th inch it wasn't worth the long ass gun, wicked recoil, and much less ammo of the T123E6.

[Jim Warford]

Here's a quick look at what they were working on...

 

Edited October 4, 2013 by Jim Warford

[Mr King]

If what that graphic says about the composite armor is true, how come they totally abandoned it on the M-60?

[Walter_Sobchak]

According to Hunnicutt "cost and the limited availability of production facilities resulted in the cancellation of this feature."

[Mr King]

According to Hunnicutt "cost and the limited availability of production facilities resulted in the cancellation of this feature."

 

 

Thanks Walter.

[Rick]

So composite armor was, and still is, designed to defeat HEAT/HEP rounds? It has no worthwhile effect on AP/APDS/APFSDS rounds?

[Ken Estes]

Did they ever mount that turret with the T123E6 (T96 turret?) to the M60?

 

What was the rationale for fielding the 105mm instead? What were the objections to semi-fixed ammunition?

 

 

 

As Dave has remarked above, the semifixed ammo reduced ammo stowage, as well as rate of fire. The British 105mm was I suppose next best to the T123E6 in all categories except for rate of fire in the 1958 tests. Both the M48 and M60 series mediums were regarded as user friendly in service. I think that would not have obtained in an M60 with a 120mm T123 series cannon.

 

How Ordnance would have made an autoloader serviceable and fit the already massive gun and installed it all in the M60 must remain a puzzle.

Edited October 4, 2013 by Ken Estes

[Przezdzieblo]

It was mostly designed versus HEAT threat. The idea was based on glass-like materials` tendency to close the crater during it`s hydrodynamic penetration, what means that jet is still attacked by pulverized particles, distrupted, weakened and slowed.

Versus HESH it acts just like spaced armour, shock is a lowered by presence of internal layer and there could be no spall.

The problem with siliceous core (which was BRL project, while sandwiches with glass were CIT idea) was major distruption of external steel layer when array was hit by full calibre AP. It was somehow found by experiments that that effect could be weakened by making that layer pretty thin.

I guess it was not tested much or even at all versus APFSDS of that time. "Arrow" and "Delta" programmes got own problems in those years.

 

To add to what was said why special armour of that kind was not accepted, read somewhere, that one of the reason was rush, with which M60 was introduced. Main specification for the "new" tank was better firepower and more fuel-efficient engine. Not a word about increased protection. When there was no need for that, and introducing it would mean additional cost and time, M60 was left with steel armour, only.

[Jim Warford]

IIRC, in live-fire testing (as part of the US T-95 program), fuzed-slica became pulverized when hit by solid-shot AP rounds. The suggested answer to the resulting inability to take additional hits, was to fill the now vacant space within the armor with concrete. While interesting, this apparently didn't work in practice.

[AdmiralB]

 

 

 

 

 

 

I wonder if the comparison has to be scrubbed in new docs - to something like "Alternative Lifestyle-Steel"?