Tankers:? about Sabot rounds

[Dar]

For all you tank veterans out there:

As I understand, sabot ammunition consists of a heavy metal core that does the actual damage when fired, and there is a jacket of material surrounding the core which is jettisoned in flight.

I have a couple questions about the jacket material:

1. What material is the jacket made out of?

2. Can you see this separate from the round in flight, i.e. does it fly up and away at much lower velocity, much like a shotgun shell wadding?

3. After firing live rounds on a firing range, is this material collected? Is it recyclable or otherwise reusable?

Goofy questions, I know, but sometimes my mind works that way...

Thanks for any answers!

[ February 14, 2002, 02:10 PM: Message edited by: Dar ]

[Gpig]

Dude! That's so bizarre. I was wondering about those same things the other day.

Also, another question comes to mind. If you were infantry dug in and defending a position with friendly tanks to your rear providing support . . . wouldn't those discarding sabot rounds be a hazard when the tanks were firing over your heads at enemy targets down range? The sabot parts would no doubt cause significant injury to any soft targets caught in the open, no? (Just from velocity alone?) Kind of suck to catch one in the back of the helmet.

Gpig

[gredeker]

Check out the graphics near the bottom of the page here:

http://www.fas.org/man/dod-101/sys/land/120.htm

It has high-speed picture of a sabot round discarding the sabot. You can even see the supersonic shockwaves.

[Gpig]

Redeker wrote:

Check out the graphics near the bottom of the page here:

http://www.fas.org/man/dod-101/sys/land/120.htm

It has high-speed picture of a sabot round discarding the sabot. You can even see the supersonic shockwaves.

Cool! Also, follow the link on that site for the M830A1 HEAT round. Check out the picture (and explanation) for the round's anit-helo capability.

Proximity fuzes for HEAT rounds to defeat Helicopters!?!?

Amazing!

Gpig

[MikeyD]

Different HVAP rounds appeared at different times.

I believe the U.S. 76mm HVAP had a lightweight casing that didn't separate from the tungsten core (like the brand-new tungsten-core 5.56 rifle rounds). The lightweight casing would disintigrate on impact leaving the tungsten core free to keep going. The German squeeze-bore rounds also didn't separate.

The Brit 6 pounder round did have a round that separated. I believe it separated like the cup-like high-drag casing (sabot - 'shoe' in French) falling away from the core in flight. The reason this was considered a close range round was because if there was any anomaly in the separation sequence (caused by slight manufacure flaws) the core could be knocked off-line.

One problem with separating rounds is you don't really want to fire over the heads of your troops. No telling where the sabot is going to fall.

[Dar]

Thanks for the replies--

Gpig--Glad to see I'm not the only bizarre, twisted mind around here!

Redeker:

Thanks for the link!

I found there the link to a page on the M829A1 120mm round, and in the M829A2 section they mention the "use of a carbon-epoxy composite for the sabot". "Carbon-epoxy" is something they're making bike frames, boat hulls, and other things from, so it sounds fairly light yet very durable.

Still, not so light you'd want to get hit by it when it's launched from the bore of a 120mm!

I have to comment on the line on that original page Redeker linked to about the bore evacuator which vaccuums out the bore between rounds. No matter how high tech we get, some things just don't change and you still need to swab out the barrel after each round!

[MikeyD]

Let me think. I've heard of extruded aluminum alloy sabots from the 70s and 80s. I honestly don't know what they made WWII sabots from... Manganese?

[USTanker]

I can only speak of modern US rounds:

1) The sabot petals themselves are aluminum. At least the ones for the M865 120mm target practice rounds.

2) You can see the petals hit the ground from 50-200 meters from the gun tube when you fire.

3) After firing, there are range sweeps where everything not living or natural is picked up and collected, within reason.

Hope this helps.

USTanker

[Dar]

USTanker--

Cool! Thanks for the reply! That answers all of my questions quite nicely.

[Splinty]

Man you tankers get all the good stuff! Our Bradleys had plastic jackets. On the other hand we had a much faster rate of fire...

[Black Five]

During tank a gunnery exercise a Marine in my platoon hit an infantry target with a sabot petal when he was shooting main gun at a tank target. There was a litte debate as to whether or not it "counted" as a kill on the infantry target. Ultimately the giant gash/hole that the petal put in the infantry target was viewed as acceptable since it was about 200 times bigger then the hole a 7.62 would have put in the target

Yes, it is very important to take into account where your sabot petals will land if your infantry are in front of your tanks, which is usually where your infantry should be.

[SGT_Gold]

Back when I was a grunt, we didn't want to be anywhere near tanks, firing or not. The muzzle blast alone is enough to make you stay away, never mind the sabot parts. If your fighting position is correctly built, you have protection from the rear against small arms and other 'light' weapons. I got out before the sabot round became wide spread so I don't know how they handle it now.

[lewallen]

one of my friends was a tank driver; just got out of the Army this year. when he was home on leave a couple of years ago, he brought me a sabot petal from a 120mm. it's about 7 inches long and 4 or so wide at the widest, made of aluminum, and fairly heavy. *definately* not something that you'd want to have smack you in the back of your head doing 1800 meters/sec. my friend says that 'crunchies' are not allowed to be within about 200m in front of the tank when it's firing the main gun due to the sabot petal danger.

~sam

[Caesar]

MikeyD's mention of the squeeze bore reminded me of a question I've been meaning to ask - Why don't we see them in CMBO. Were they only used on the Russian front?

[gunnergoz]

Originally posted by Caesar:

MikeyD's mention of the squeeze bore reminded me of a question I've been meaning to ask - Why don't we see them in CMBO. Were they only used on the Russian front?

Some one may correct me on this, but I believe that the required tungsten was in short supply in Germany and the rounds were only in production for a brief while. I think they might have made it to Africa, and probably to the Russian front also, but probably were out of production by the time of the Normandy battles in '44.

[John D Salt]

Originally posted by MikeyD:

Different HVAP rounds appeared at different times.

It is probably worth preserving the distinction between APCR, APCNR and APDS rounds rather than lumping them all together as "HVAP". Effectively, any round deployed by the USA during WW2 designated as HVAP was APCR.

I believe the U.S. 76mm HVAP had a lightweight casing that didn't separate from the tungsten core (like the brand-new tungsten-core 5.56 rifle rounds).

Yup, that's APCR, same as the German Panzergranate 40 and the Soviet podkaliberniy rounds. I believe that APCR rounds were produced for the 6-pounder and 17-pounder, but never used in action. An experimental APCR round for the Sherman's 75mm M3 was used experimentally, and penetration performance figures are given in Hunnicutt's "Sherman" which indicate that it would have had a slight edge in penetration over the 3-inch or 76mm guns firing APC. That would make the Sherman 75 a pretty fierce beast, but the commander of 22 Armoured Brigade after Villers-Bocage wanted an APDS round for the 75mm Mk V (the British equivalent of the M3). CM:BO players who like to play the Germans can presumably be glad that no such round was ever developed.

The Brit 6 pounder round did have a round that separated. I believe it separated like the cup-like high-drag casing (sabot - 'shoe' in French) falling away from the core in flight. The reason this was considered a close range round was because if there was any anomaly in the separation sequence (caused by slight manufacure flaws) the core could be knocked off-line.

Both pot and petal sabot were developed for the 6-pounder, and are illustrated in Bovington Tank Museum's "Fire and Movement" booklet. I was under the impression that all the amn issued for service was petal sabot, but can't recall seeing this stated anywhere. Do you have a source for the issue of pot sabot?

I'd be interested in knowing where you heard or read that 6-pounder APDS was "regarded as a short-range round". OA papers I have seen at the PRO indicate that the maximum enagement range was advised as being 800 yards, but that was controlled by hit probability (and the pretty demanding criterion of a 50% chance of a first-round hit) and no different for APDS or APCBC. I understand that early 17-pounder sabot had some accuracy problems, but have never heard so for other APDS rounds.

All the best,

John.