OT - Guy throws a grenade down the barrel of a tank

[Jim D Burns]

ORIGINAL: Chickenboy
What if there was an HE round loaded into the tank's cannon when a grenade was dropped into the far end? Couldn't a fragment detonate the round, blowing out the breech and resulting in an enflagration within the turret?

Would depend on how the HE round was primed. I know some US grenades used by grenade launchers are primed mid-flight by the centrifugal force the spinning grenade produces. I assume some HE rounds use similar methods to prime the shell mid-flight, but more than likely most are primed by the tanks loaders when the shell goes into the breach. If the shell was primed, then a grenade blast in the barrel could easily set it off.

But these days shells have so many different firing mechanisms, it would take a military arms master to know what all of them needed to happen for them to go off. Some use timed fuses, others use firing pins, and some go off based on a shells altitude. One thing's for sure though, an HE shell that isn't primed would have little chance of exploding if the shell itself wasn't somehow breached so the explosive could be subjected to something to set it off.

Jim

[wdolson]

I doubt the shells are primed before firing, the concussion of firing could set them off.

[RevRick]

I doubt that the grenade did any damage to the barrel or the breech..Gun breeches and barrels are designed to sustain a lot more force than that of a grenade. Someone do the math - a 5" x say 11" volume for the propellent charge of a 127 mm round versus the explosive volume of a hand held grenade. It would seem extremely unlikely that a hand grenade would generate anywhere near the same energy! The first 'explosion' looks way to much to me as if a round had been fired. It almost looks as if the first grenade went off at the same time the gun was fired - and the subsequent grenade went into the compartment through an open breech during a very slow reloading process. It looks as if the subsequent grenade went of inside the compartment.

Of course, it also could have been rigged, because it looks to me as if the hatch was not down on the tank anyway.

Just my tuppence worth, but something seems amiss in the whole shebang!

[tigercub]

grenade goes off in barrel crew opens to take a look second grenade drops inside? BOOM...or its all a stunt!

[Sredni]

What type of tank is it?

[AW1Steve]

Two questions for a "land warfare ignoramus". So please be gentle! [:D] 1) would an open breach make a difference? and 2) the Soviets used an auto-loader for their tank guns to save space. Would this make a difference as far as the warshots being "primed"? And would the auto-loader in some way make the tank more vulnerable to "sympathetic" explosions? [&:]

[Canoerebel]

ORIGINAL: tigercub
grenade goes off in barrel crew opens to take a look second grenade drops inside? BOOM...or its all a stunt!

If I'm in a tank and a grenade goes off in the barrel, the last thing I do is open the breach to look inside (assuming you can see inside the barrel from the interior). The first thing I do is get the heck out of dodge. If the tank is imobilized and unfriendlies are firing at me and seem to have heavy stuff, I either call for close by help or abandon the tank.

[oldman45]

I can't imagine the sound they would have heard in the turret when the grenade went off. I do know the last thing that would have crossed my mind would have been "lets open the breach". [;)]

[Bearcat2]

Former tanker; if the breech is closed[and it always is unless you are loading a shell], and it is a fragmentation grenade, it would not have much effect, but you would have to clean out the debris before firing the main gun. A thermite grenade is a different story.

[Chickenboy]

ORIGINAL: Termite2

Former tanker; if the breech is closed[and it always is unless you are loading a shell], and it is a fragmentation grenade, it would not have much effect, but you would have to clean out the debris before firing the main gun. A thermite grenade is a different story.

Termite2-would a frag grenade likely explode a loaded HE shell in the breech? Cause a propellant leak / fire?

[Bearcat2]

I do not think so; but it may be possible. It depends on the firing mechanism and which type of HE rd. The possibility of dropping a grenade into a loaded gun is remote to begin with. It only takes a sec to load, so they are unloaded until they get a target so that the proper ammo is loaded.

[budman999]

Speaking as an artillery man - generally artillery shell fuzes are armed after two things happen: a certain amount of force is generated on the fuze as well as a certain segment of time has to pass.
I would think that a tank gun shell would follow similar safety principles.
As well the gun barrel of any modern cannon is more than capable of handling a typical grenade explosion.

[Jonathan Pollard]

According to the Cavalry Field Manual (1941-42), "Grenades, available to all elements of Cavalry, are effective weapons for use against mechanized and armored vehicles." [p.148]

http://www.cgsc.edu/carl/docrepository/FM2_15.pdf

[:D]

[wdolson]

I recall in Band of Brothers at Normandy a team from the 101st were tasked with taking out some artillery pieces behind the beachhead. When they got to the guns they dropped grenades down the barrel to disable them. From what I've read the depiction in the mini-series was very close to the way it actually happened.

I think one of the guns was back in operation the next day, but the rest were permanently knocked out by the grenades.

The fragments from the grenade would bury themselves in the walls of the barrel. At minimum the barrel would need a thorough cleaning before being used again. I would think the blast could also weaken the barrel depending on where it is in the barrel. At the bottom of the tube would be in the strongest point which is designed to take a blast, but in the middle of the barrel it could weaken the walls of the barrel.

Bill

[witpqs]

ORIGINAL: wdolson

I recall in Band of Brothers at Normandy a team from the 101st were tasked with taking out some artillery pieces behind the beachhead. When they got to the guns they dropped grenades down the barrel to disable them. From what I've read the depiction in the mini-series was very close to the way it actually happened.

I think one of the guns was back in operation the next day, but the rest were permanently knocked out by the grenades.

The fragments from the grenade would bury themselves in the walls of the barrel. At minimum the barrel would need a thorough cleaning before being used again. I would think the blast could also weaken the barrel depending on where it is in the barrel. At the bottom of the tube would be in the strongest point which is designed to take a blast, but in the middle of the barrel it could weaken the walls of the barrel.

Bill

They used thermite grenades. And, while it apparently was not remembered for certain, the belief is that they used them to fuse the (sorry I don't know the proper names) traversing and elevating mechanisms used to aim the guns.

I have personally wondered if the thermite grenades might have been used to destroy the interrupted screw (is that the right term?) that seals up the breach.

EDIT: Come to think of it I was recalling the story of the Rangers who had to go and find the guns they expected to find in bunkers overlooking the shoreline.

[Blackhorse]

A few comments on the observations above:

1. Most modern tanks carry few true HE rounds. The most common anti-tank rounds are inert, except for the propellant. Most tanks also carry HEAT, which is designed to detonate after a distance, on impact, with the blast going directionally forward. So even if a grenade triggered a sympathic detonation, most of the blast effect would head down the barrel.

2. Depending on doctrine, tanks have been known to travel with a round in the tube. On exercises in West Germany in the mid-80s, practicing against a Warsaw Pact invasion of the Fulda Gap, US tanks might 'battle carry' sabot. The theory was, enemy tanks (or helicopters) were the main threat, and a round in the tube might enable you to engage first. If a lesser threat appeared first, we could fire off the sabot anyway, then load the most appropriate ammunition.

3. A thermite grenade down the tube would definitely hurt a tank. If it settled at the base of the tube, it would eventually fuse the barrel and breechblock. More effective than a fragmentation grenade, I think. But it would take some time.

4. Grenades were considered effective against tanks in WWII -- US infantry doctrine was to get a bundle or a bag of grenades and try to throw them against the side of an enemy tank to break the track, or blow off a roadwheel. Not for the faint of heart.

5. witpqs: interruptor screw, methinks.

[veji1]

Assuming this video is legit one would also have to account for poor maintenance of syrian equipment, insufficiently trained crews, etc. opens up the possibilities of damage.

[castor troy]

ORIGINAL: Blackhorse


2. Depending on doctrine, tanks have been known to travel with a round in the tube. On exercises in West Germany in the mid-80s, practicing against a Warsaw Pact invasion of the Fulda Gap, US tanks might 'battle carry' sabot. The theory was, enemy tanks (or helicopters) were the main threat, and a round in the tube might enable you to engage first. If a lesser threat appeared first, we could fire off the sabot anyway, then load the most appropriate ammunition.

tanks would engage helicopters with their main gun? [&:]

[Tophat1815]

ORIGINAL: castor troy

ORIGINAL: Blackhorse


2. Depending on doctrine, tanks have been known to travel with a round in the tube. On exercises in West Germany in the mid-80s, practicing against a Warsaw Pact invasion of the Fulda Gap, US tanks might 'battle carry' sabot. The theory was, enemy tanks (or helicopters) were the main threat, and a round in the tube might enable you to engage first. If a lesser threat appeared first, we could fire off the sabot anyway, then load the most appropriate ammunition.

tanks would engage helicopters with their main gun? [&:]

Yes that is correct. Low flying helo's trying to use ground cover,trees,terrain elevations any obstacle to stay out of line of sight,stay under effective shoulder fired anti-air missiles and combat air patrols/sweeps ability to engage find themselves in the engagement bubble of a tanks main gun. That is one reason for a tank to sashay about with a HEAT round up the spout.

Example: Armor column moving up to "the line" is interdicted by helo that pops up from tree cover to launch ATGMS,if the helo is within 35 to 50 degrees of elevation tank engages with main gun.

[morganbj]

This is, of course, the correct answer.