Jericho: Any way to fire a mortar round out of a tank?

[Biscuitsjam]

In the American television series Jericho, America's cities are all destroyed by nuclear bombs and the people in the countryside have to struggle to survive. The town of Jericho ends up acquiring an Abrams tank, which they use to defend themselves against the warring neighboring town of New Bern.

 

Jericho captures a home-made mortar round (120mm?) and successfully fires it in the 120mm main gun of the Abrams. Is there any way to do this?

 

There are a lot of obvious problems and such a round certainly wouldn't fire without some extensive modifications... Still, given a few weeks and some intelligent people, could you figure out how to make it work? If so, how?

 

 

 

By the way, I was a loader on an M1A1 tank. I know more than a little about them, but I'm nowhere near being a Master Gunner either.

[Wobbly Head]

If it is possible without the knowing the speed of the round to caculate the trajectory and the M1A1 having a smoothbore gun the chances of hitting what you are amming for would be next to nil.

Edited May 12, 2007 by Wobbly Head

[gewing]

If it is possible without the knowing the speed of the round to caculate the trajectory and the M1A1 having a smoothbore gun the chances of hitting what you are amming for would be next to nil.

 

 

 

if it was a fin stabilized mortar round and they were only lobbing it out a short distance... Maybe use a stub case and a bunch of black powder?

[Manic Moran]

if it was a fin stabilized mortar round and they were only lobbing it out a short distance... Maybe use a stub case and a bunch of black powder?

 

This got a brief mention on the Jericho thread.

 

The big question is ignition of the propellant. With the breech closed, how does one ignite it? The obvious solution is a lit fuse and a timer. Light the fuse, shove the round into the breech, manually trip the block release, and wait.

 

There's no particular reason a mortar round can't be fired from a tank cannon: The HE round for the 120mm gun is basically a modified mortar round put into a shell casing. Think about it, a 120mm mortar is a long smoothbore tube. A 120mm tank cannon is a long, smoothbore tube. Not much of a difference for the round.

 

If the mortar round is not perfectly 120mm and instead a bit smaller, it's still not going to be too critical as long as there is sufficient propellant gasses to propel the round forward, perhaps with wadding. We're not exactly talking about point targets here. Friend of mine put a magazine of 357 rounds down my .40 cal barrel once, he still managed to hit a man-sized target at 10 yards.

 

NTM

[Biscuitsjam]

One of the potential issues is the size of the mortar round. If the gun tube is 120mm and the mortar round is 120.5mm, for instance, there is going to be a big problem... If the mortar is significantly smaller (say 105mm), you have a whole other slew of issues.

 

Another potential problem is the chamber size. While the main gun's bore is only 120mm in diameter, the chamber is MUCH bigger. The mortar round is neither long enough nor big enough around to fit properly in the chamber, and if it is just rolling around in the bottom, won't line up with the bore at all. I don't think it is really feasible to put a mortar round anywhere in the breach itself, so it would need to be pushed forward all the way into the gun tube. Then, you'd need something behind the rear of the mortar round to prevent the case from flying back or blowing out when fired.

[Kensuke]

Any way you cut it, it was a stupid scene.

 

The solution would have been to have 120mm rounds in the tank when they got it. My understanding is that the fake Marines liberated it from a real Marine unit deployed near a refugee camp.

 

My only guess is that the writers wanted to drive home how oh-so-resourceful the people of Jericho are.

 

- John

[FOXMG]

There's no particular reason a mortar round can't be fired from a tank cannon: The HE round for the 120mm gun is basically a modified mortar round put into a shell casing. Think about it, a 120mm mortar is a long smoothbore tube. A 120mm tank cannon is a long, smoothbore tube. Not much of a difference for the round.

 

Just being picky, but there is no 120mm HE round for the M1 series.* A HE round is quiet different than a HEAT round, I dont think (that I know of) that there are any HEAT rounds for mortars. Anyways my point is that the HEAT round is deffinately not a modified 120mm mortar round, if thats what you meant.

 

*I recall that Israel fielded a 120mm HE round for its tanks.

 

 

 

As for the rest of the thread the major issue I see are the ones stipulated above, that a mortar round would never reach into the forcing cone area of the breach.

 

Second thing is that the escaping gases would come back into the tank, lowering velocity substantially. The breach has to have a round in it to seal, the stub base actually seals the breach, not the breach block. If you dont have a stub base you have a quite a large hole at the top of the breach, there will be no pressure built in the chamber.

 

The last thing is that a mortar round has no rotater bands, and will allow gas to escape along the edges of it, this would be solved with some type of wadding I think though.

[Rickard N]

The Swedish 120mm HE-round is a derived mortar round though. I think Manic was talking about 120mm HE-rounds in general.

 

/R

[Manic Moran]

The Swedish 120mm HE-round is a derived mortar round though. I think Manic was talking about 120mm HE-rounds in general.

/R

 

Which is exactly what I was referring to. Due to the wonder which is ammunition commonality (not least because the German 120mm and US 120mm are as near as makes no difference to being the same gun), you can fire that converted mortar round out the end of the American tank's gun tube.

 

NTM

[Briganza]

Push the bomb into the barrel beyond the chamber. When fired the obturating ring will seal the barrel. Use petrol as a propellant, plastic container with a pint or two stuffed in behind. Place a large tin packed to the diameter of the chamber behind the petrol. Then fill the rest of the chamber with expanding foam and close the breach. The only problem is detonation, could have a mobile connected to an electric det? But the are the phones still working?

 

They would be better off using a plastic drainpipe dug in the ground and surrounded by concrete.

 

Detonation would still be the problem and would it fuze the bomb?

[jaro]

i was quite suprised by that part. Jericho was one of my favorite shows. I dont understand why they just didnt roll over all those trucks with a tank... New Bern didnt had anything to stop M1A1... even without ammo, 70t vehicle is unstoppable if enemy is armed just with rifles.....

[Cromwell]

The Merkava does it all day, though not through the barrel.

[Vasiliy Fofanov]

The Merkava does it all day, though not through the barrel.

 

The weapon caliber is however, shall we say, a bit smaller

[Jim Martin]

First, I couldn't see a tank being deployed without rounds, during civil unrest. Second, I was thinking what a tune I could play on those soft skins and dismounts just with the coax from the tank.

[SCFalken]

If New Bern is mass-producing mortar rounds (and mortars?), what are they using for the warhead filler and launching charges?

 

Black Powder for the charges, likely, but what for the warheads. It's not like you can use ANFO*. TNT?

 

 

 

Falken

 

*-although a farm town like Jericho likely has the makings of some hellacious ANFO mines and IEDs...

Edited May 15, 2007 by SCFalken

[AETiglathPZ]

Wow, didn't know about this show until this thread. Just downloaded and watched the series these past 4 days.

 

The M1A1 was supposedly out of ammo. so, no main gun rounds, coax and .50 cal.

The single mortar shot was at close(100 meter?) range.

The motar round looked smaller then 120mm.

The gunner primary sight doors were closed.

The gunner could have used the secondary sight.

 

'The big question is ignition of the propellant. With the breech closed, how does one ignite it?'

 

Pop it into the barrel. Put some rags or something in it to prop it steady. Wire the round to the ignition using some wires. Crank the master blaster. Shouldn't be too hard since some of the characters know how to rig dynamite used in the mines.

 

To bad Hawkins didn't have some 7.62 or none was captured. Coax would be fun.

[JWB]

If New Bern is mass-producing mortar rounds (and mortars?), what are they using for the warhead filler and launching charges?

 

Black Powder for the charges, likely, but what for the warheads. It's not like you can use ANFO*. TNT?

Falken

 

*-although a farm town like Jericho likely has the makings of some hellacious ANFO mines and IEDs...

ANFO can be used with a rocket which can be propelled by black powder. BP can be produced ahelluva lot more easily then nitrocellulose. Problem with nc is it requires huge amounts electricity. But AN requires large amounts of electricity to produce also. New Berne seems to be able to produce some but I doubt enough to produce any meaning full amount of TNT or AN or NC.

[X-Files]

The New Bern mod was unassing the AO in disorder, there was no driver was in the deuce and a half but they felt inclined to waste a fantasy round anyway. The scriptwriters must have needed a big victory boom.

 

Waste of ammo, waste of film stock. Let the zombies devour the town residents and series producers in the finale.

[JWB]

The New Bern mod was unassing the AO in disorder, there was no driver was in the deuce and a half but they felt inclined to waste a fantasy round anyway. The scriptwriters must have needed a big victory boom.

 

Waste of ammo, waste of film stock. Let the zombies devour the town residents and series producers in the finale.

Yep, The ratings for that show must be plunging and the producers felt it was time to "jump the shark".

[jaro]

Guys, i think you are overreacting... that M1A1 even wasnt real Abrams... it was Vismod CHieftain...

[Vasiliy Fofanov]

Guys, i think you are overreacting... that M1A1 even wasnt real Abrams... it was Vismod CHieftain...

 

6 roadwheels was a dead giveaway. Still a pretty decent vismod all things considered...

[DougRichards]

Guys, i think you are overreacting... that M1A1 even wasnt real Abrams... it was Vismod CHieftain...

 

I haven't seen the episode, but wasn't there a few vis-mod Centurions (ex Australian) running around Hollywood trying to look like Abrams (I am thinking of 'Courage Under Fire').

 

It is more likely that one of those would have been used rather than vismod another vehicle.

 

Anyway, what was the target of this mortar round? If it was an armoured vehicle, then I wouldn't count too much on an effect, if unarmoured, why not just use the tank as a weapon and ram? It is as if a lot of people have forgotten that thanks don't just depend on their weaponry for effect.

[Burncycle360]

I haven't seen the episode, but wasn't there a few vis-mod Centurions (ex Australian) running around Hollywood trying to look like Abrams (I am thinking of 'Courage Under Fire').

 

I seem to remember watching a documentary about a group in california that maintains and vismods armored vehicles specifically for movies

[jaro]

I haven't seen the episode, but wasn't there a few vis-mod Centurions (ex Australian) running around Hollywood trying to look like Abrams (I am thinking of 'Courage Under Fire').

 

It is more likely that one of those would have been used rather than vismod another vehicle.

 

Anyway, what was the target of this mortar round? If it was an armoured vehicle, then I wouldn't count too much on an effect, if unarmoured, why not just use the tank as a weapon and ram? It is as if a lot of people have forgotten that thanks don't just depend on their weaponry for effect.

 

 

nope, definitelly Chieftain, i saw all parts of Jericho, and they showed pretty clearly whole tank - front hull of Chieftain is too genuine....

[jaro]

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