MOBAT, WOMBAT, CONBAT | Anti-Tank Chats

welcome to the latest in our series of anti-tank chats and this time we'll be talking about this weapon the bat British armies Battalion anti-tank gun 120 millimeter recoilers rifle this video has been made possible by our supporters on patreon our YouTube members and our super thanks donors please join them if you can and support tank Museum and thanks for watching story really starts with a very strange looking post-war vehicle the American M50 ontos now on toss is Greek for thing and this object it's a it's a very odd looking two-man uh track vehicle with 606 millimeter recoilers rifles on top it came out of something called project Vista which is named after the Pasadena hotel in which the initial meeting took place this envisaged Western Europe the north German plane the folder Gap places like that being defended from the vast hordes of Warsaw pack tanks by minefields infantry strong points and small cheap Expendable Vehicles like the ontos fitted with the M40 recoilers rifle although the recall this principle had been known for some time but it's military application really dates to just before the first world war and an American naval officer called Cleveland Davis and he came up with a concept for a recall this weapon now the whole recall this idea is extremely useful because if there is no recoil the weapon doesn't need to be on a big heavy mount it doesn't need recall cylinders and that's a considerable Advantage if you want to do something like managed on an aircraft and it should Aid because it's very lightweight it's portability Davis achieved this by producing a weapon that used two propellant charges which when detonated pushed the projectile in One Direction while an equal weight of buckshot went down the other it was rejected for ground use but interestingly it was adapted for use on aircraft and the thought was it could be used against u-votes it was experimentally suggested to something for hunting zeppelins the one thing here being though that the pilot would need to make sure the Buckshot charge didn't damage his aircraft the Davis weapon these days is is really remembered just as a curiosity but what was key to improving the recall this principle was work done by the German almonds manufacturer crook the [ __ ] designers realized that you didn't need Buckshot you could actually use propellant gases because it didn't matter what came out of the rear of the weapon as long as the actual charge was balanced and they're working to produce a lightweight gun that would fire a large caliber charge so putting that very simply a projectile goes one way and the propellant gas goes the other The Secret of this is something called Venturi which is a narrow section and that speeds up the gas before it's expelled through a cone-shaped funnel at the rear of the barrel the second important element in the design was uh the case itself now this needed to contain five times the propellant um to the weight of Rand of a normal weapon the propellant gas needed to escape backwards but the problem is that the propellant itself would not combust properly unless it's under pressure so there's an opening at the rear but that is closed temporarily with a baker-like disc to enable the propellant combust when that bursts propellant gas goes backwards shell it kicked forwards and the whole thing works the grip Design Incorporated a lightweight carriage a rear based breach and the use of large Caliber hollow charge shells which meant that it didn't compromise the low velocity of the gun itself what this led to was the Leicester schutz LG 40 a 7.5 centimeter or lightweight infantry gun which was used by German power troops Mountain troops and it saw its combat debut in the invasion of Crete in 1941. the Crypt design set the standard for modern recoilers rifles for the British the development of recall this rifle was largely down to one man Sir Charles deniston Bernie retiring from the Royal Navy as a commander Bernie had worked on quite a number of projects including the r100 airship but he'd also begun to explore the possibilities of the Davis principle independently of the Germans starting off with a four-bought punt gun by 1944 Bernie had moved from initial 20 millimeter weapon up to a larger 88 millimeter example this weighed in at 75 pounds which was viewed as being light enough for a single soldier to handle although to judge by the images of the way they had to braced themselves under the weight of the thing I'm not entirely sure that was true the most Innovative part of this design was the use of a large caliber high explosive shell to attack armor this employed what would become known as the squash head principle the shell impacts on the armor and the quantity of he inside spreads and deforms before it's detonated by base fuse this sends a high velocity compressive shock wave traveling through the armor plate until it reaches the air on the other side on contact with the air the shock wave is reflected backwards and it meets more secondary shock waves coming forward these then combine it's this combined shock wave that then comes forward it over matches the strength of the armor plate and it detaches a large scab of metal from the interior this detached scab moves anything from 30 to 130 meters a second and it's between 25 and 50 percent bigger than the diameter of the Hesh Warhead the impact of the Hesh Warhead have a massive concussive effect smashing fittings inside the vehicle and the impact of 150 millimeter metal scam whirling forward into the filet compartment would have a hideous effect on the vehicle and its crew by 1946 Bernie had designed a 120 millimeter recall this weapon and he was experimenting with the use of Rocket assisted Munitions and the board of Ordnance had ordered 80 trial rounds for this it was this design that was to become the basis for the 120 millimeter Battalion anti-tank gun of 1950. the main improvements adopted the use of the crop single Venturi on breech block and a plastic bursting disc in the base of the cartridge entering service in 1953 the first L1 120 millimeter bats were somewhat on the heavy side I mean they weighed in well over a thousand kilograms but that's still a third of the weight of the 17 pounder anti-tank gun they were replacing and they had a lower profile even with a protective gum Shield under a thousand kilograms is still quite a weight and they were quite a handful for a three-man crew to handle concerns with the weight of the bat led to the introduction of the L2 modified bat the mobat now this lost the shield and traversing gear and it managed to reduce the weight by about a quarter and that enabled the gun to be towed behind a Land Rover we're fortunate here in that we've got examples of three three different weapons from the bat series we have wombat mobat and then this one this is the L7 combat and this is an upgrade from earlier weapons essentially what you've got here are five different components Barrel mounts for the ranging gun sighting gear the carriage and then down at the back end obviously that is the breach starting at the front business end uh there is a towing eye and then pair of handles to enable the crew to move the weapon around and then as you come down the barrel it's really difficult to see there's actually something I really I very much like here there's an engraved Royal Crest with the cipher about Lake Queen Elizabeth II and that's something they were doing in Tudor time so I'm really not it's really nice to see that's carried on just behind that these are the mounts for the l40a1 ranging gun now what that was was an M8 U.S manufactured semi-automatic rifle with a magazine of 20 Tracer rounds that is an effective ranging tool because out to 350 meters there's Trace arounds and obviously you can see them in Flight uh will follow the same trajectory as the Hesh round when you fire it it was better than what came before certainly which was a Bren gun was actually mounted on a bracket on this side the 303 rounds from the Bren didn't follow the same trajectory so he really didn't do the job quite as well here on the right hand side of the weapon we have the Gunner's position and this is the armed which the sighting apparatus would be fitted so you have an iron sight here for uh course aiming and then there's a bracket for a telescopic site now we don't unfortunately have one of these but the L6 wombat would have been fitted with the number 75 site which is three times magnification and that would enable the Gunner to engage a moving Target up to about 1 350 meters and a stationary Target out to 2000. running through the Gunnery controls down here is the elevation wheel that will give the Gunner up to 17 degrees of elevation and 8 degrees of depression now the Traverse gear has been removed so that's free running and that is a free 360 degree Traverse just here this is these are the firing controls and there is a cable operated trigger which I've got my thumb on that were far around from the ranging gun and then you've got the safety catch just here just turn it around onto fire and this is the firing button and when you press that the hash round goes down the barrel look at the breach uh it is a vertically operating breech and you can open it from either side using these levers all you need to do is depress the lever plunger and then pull lever backwards and that actually drops the breech block down with breach open the loader will take this massively heavy as a one piece round it weighs over 60 pounds lay that down on the tray here Push It Forward into the breech and then close the bridge by pushing the levers forward when the weapon's fired the Hesh round will travel to the Target at around about 462 meters a second with the use of the spotting gun it's really very accurate and the rate of fire is four to five rounds a minute the crew obviously had to be mindful of the huge back blast that would be extremely dangerous and it would also tend to give the position of the gun away the weapon as you see is in Towing mode so that means the Traverse gear is locked so the barrel won't swing around uh you've got a pair of quite meaty uh cross-country pneumatic tires for ease of Towing and then a pair of hand brakes worn on either side looking at the ammunition this is a sectioned training bat Hesh round 120 mil and coming forward from the back you've got the base fuse here that's designed to detonate at the optimum moment on impact of the Target and that will set off this red material which is the high explosive now the whole thing about this is the round needs to hit the target and the Squash head effect comes into play so the front this area here is noticeably thinner that's to allow the round to impact on the Target and for the high explosive to spread before detonation it's important that the high explosive is insensitive enough not to burn through prematurely on impact with the target before the base fuse can detonate that would cause what's called Reverse Impact detonation and the shock wave would flow away from the target rather than achieving the Hesh effect um it's further assured by the fact we've got an inert black filling in the nose of the shell that absorbs some of the impact and it makes sure the explosive will spread correctly the last iteration of the 120 millimeter L6 bat series arrived in service in 1964. the weapon of magnesium the wombat I think that's a pretty convoluted acronym if I'm honest and I do wonder whether somebody had a thing about Australian marsupials but as the weapon ended up being used by the Australian Army I suppose there may be a link the weapon used lightweight magnesium alloy in the carriage and high grade steel in the barrel and this reduces the total weight by up to 65 percent to a very svelte 295 kilograms dimensionally the wombat also shows this reduction uh it shrinks in width to 85 centimeters and the height is dropped by reducing the wheels by 23 centimeters in diameter it was also fitted with a new circular ring locking breech which swings open to the right the reason for this reduction was to enable the wombat to be poor team mounted long wheelbase Land Rover now the thinking behind this is the Infantry of getting increasingly aware of the threats of the nuclear Battlefield having a weapon towed behind you would slow you up to a considerable degree another solution came from the Infantry trials and development unit who by 1967 had come up with a simple six bolt Mount so the wombat could be fitted to an fv432 armored personnel carrier the fe-432 could carry 12 rounds uh the porty mounted Land Rover carry six the typical organization of an infantry anti-tank platoon was six wombats in three sections before this mountain capability infantry back teams were trained to far from prepared gun positions from gum pits but by the late 1970s 1980s things are changing and the wombat is becoming obsolete we're getting the introduction of uh recall this short range anti-tank weapons like the cargo staff and also wire guided anti-tank missiles thank you for watching if you've enjoyed this please subscribe or if you can support us on patreon and we look forward to seeing you at tankfest

Channel: The Tank Museum

Views: 210,484

Keywords: Bovington, Dorset, Tanks, Tankfest, tanks, tiger, chieftain, tank museum, second world war, world war two, top five tanks, tank chats, david fletcher, british army, tiger 131, royal armoured corps, tank regiment, RAC, tank museum bovington, tanklife, bovingtontank museum, military history, ww2, ww1, armoured car, tankchats, army, veteran, wwii history, world war 1, world war ii, war history, royal navy, ww2 history, royal air force, wwii museum, wwi, ww2 tanks, ww2 weapons

Id: 8LHsve7Y6FQ

Length: 16min 41sec (1001 seconds)

Published: Fri May 05 2023