PIAT: Part One

Anti-Tank, Custom builds, PIAT, Products, Weapons, WWII

Using CAD has started to become a bit of a habit… The PIAT was no exception!

I wanted to use a massive spring in this, even though there are more practical ways of firing a shell it’s true to the original and has some serious man-points attached!

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This is actually my second design, my initial design was slightly different internally and used the direct power of the spring to drive the projectile. Although this worked in my initial experiments, once I made the piston captive (necessary to stop half a kilo of steel from smacking someone in the face) the ball barely fired. The redesign will use a CO2 shell or blank-firing mechanism depending on use._DSF5532

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The buttplate is 2mm folded steel, welded into place purely for aesthetic reasons, as the original was stamped steel. Once polished up that is how it will look.

Sight units next: foresight and rear sight are different shapes but much the same idea. I fitted them together before welding so that they would line up correctly.

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With these two units complete, I could make the trigger mechanism. This is my version one, I have since then made some refinements that will make it smoother to use.

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One spring resets the second sear. You can see in this photograph that the spring pushes the sear up very high, this ended up being a problem as the force of the mainspring would make it almost impossible to actuate the mechanism. The next version fixes this by keeping the second sear at a usable height against the piston.

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All welded in place, ready to be cleaned up.

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Testing rig prior to making the piston captive. I also ended up making lightening cuts to the piston to improve travel speed. You can see the size of the spring in this shot, at one point I was unfortunate enough to be in the way of the piston when the sear slipped and it gave me a smart upper-cut to the chin. Fortunately it was only at half-cock otherwise I would have been in a pretty bad way!

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So, I’ll admit I have skipped a bit ahead here but the back end of the launcher was pretty well finished at this stage except for some adjustments to be made just before completion. Like the original, re-cocking is achieved by standing on the buttplate and lifting the rest of the launcher. I set to work on the fore-end that would hold the projectile.

This is a spare piece of mild steel tube I had left over from a previous build. I marked out the cutout on the top and removed it with an angle grinder.

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I then cut out a steel disk for the back of the head, drilling the centre for the ‘spigot’ (the steel rod that in the real version would fire the explosive charge in the shell) to come out of. This could then be welded in place along with the collar that attaches the head to the body. Five screws distributed around the circumference hold it in place.

As well as the mainspring, at this point I added a smaller spring that sits around the spigot to absorb the shock of the piston finishing its travel. This spring just bounces freely off the back of the head.

As I said at the start, this is the point where testing became less successful. Without the weight of the piston carrying the tennis balls I was firing originally they only just left the barrel. As a result, the design is being modified to take CO2 grenades. In the longer run it will also be able to fire blanks for re-enactment purposes.

 

 

If you are interested in this build, have any questions or would like a build of your own, let me know! Our email is: enquiries.vintageairsoft@gmail.com or you can contact us through our Facebook page!

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Projector, Infantry, Anti-Tank

Anti-Tank, Cold War, Custom builds, PIAT, Products, Weapons, WWII

A_PIAT_(Projectile_Infantry_Anti-Tank)_in_action_at_a_firing_range_in_Tunisia,_19_February_1943._NA756

At the beginning of the Second World War, every major nation had a tanks of some description. What very few nations had was an effective way for infantry to counter them. At the time, the only way to disable a tank was with a risky sprint and throwing of a satchel charge (unofficially) or use of an anti-tank rifle. However anti-tank rifle technology was a hangover from the Great War and was already pretty outdated by the quality of armour on most tanks and was only useful against light armour and soft-skinned targets.

After the Battle of France, the British Army studied reports of infantry/tank contacts and failed to find a single example of the Boys anti-tank rifle actually destroying a tank.

Boys_Mk_I_AT_Rifle

The Projector, Infantry, Anti-Tank or PIAT was what Britain came up with. Designed by Major Jefferis of MD1, the toy box of the War Office, with a great deal of input from Major Blacker of Blacker bombard fame. The basic design was that of a Spigot mortar, adapted for use as a direct-fire system.

A Spigot mortar uses a combination of a hefty spring and a small explosive charge at the base of the projectile to operate the weapon. The warhead, instead of sitting inside a barrel as per a regular mortar, sits over a small diameter tube and is actuated by a bar hitting the priming cap. A diagram explains this far better than words do:

British_Piat_schem.jpg~original

In this diagram you can just make out the guide tube in the centre of the projectile support. The missile slots over this and the firing pin travels through it.

piatgordon2

The effectiveness of the PIAT in use is much debated. Some sources cite that ammunition was unreliable, others that accuracy was a major issue at any kind of range and many that recoil was truly horrendous (some users said that you deserved the Victoria Cross just for firing it!). However a study of Canadian Officers ranked the PIAT as the number one most “outstandingly effective” weapon, above even the Bren, so in spite of its many foibles it was clearly well enough liked!

The PIAT was used by British and Empire forces throughout the war both as a direct fire anti-tank weapon and indirect fire support weapon. It was also given to the Soviet Union as part of lend-lease, dropped to partisans throughout Europe as well as by Israel post-war. It was last used officially by the Australians at the start of the Korean War, but it was quickly replaced.

The_British_Army_in_North-west_Europe_1944-45_B11928

As progress occurs we shall of course keep you posted on this build (follow the blog to help you keep track!), if this has inspired you to want a project of your own or you have any questions, do drop us a line! Our email is: enquiries.vintageairsoft@gmail.com. Also, ‘Like’ our Facebook page for updates and interesting articles.

LAW M72 update

Anti-Tank, Cold War, Custom builds, LAW, War on Terror, Weapons

I’ve been working quite hard on the LAW rocket launcher this month so far, with lots of plastic work!

I had the fortune to find two pieces of pipe which had corresponding inside and outside diameters, allowing one piece to slide snugly inside the other. My client had a model of an earlier type of LAW and had sent me the trigger mechanism housing from it (in green below) to work from.

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I created a wooden mould from photographs of the A7 in order to be able to form this complex shape. My initial idea was to build a vacuum former but before going to the expense of doing that I thought I’d have a go at forming with a heat gun…
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Pushing the plastic into the former.

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My second attempt, getting the sharp edge in front of the trigger is pretty well impossible with this technique without splitting the plastic or creating a crease so it looks like I’ll have to build a vacuum former after all!

I also ran some tests on nerf balls to see how they performed ballistically. When put in the end of the 50mm bore tube I was planning on using for the barrel it barely fell out the end when the grenade was actuated. I then tried a smaller bore pipe which sat just around the end of the nerf ball. This produced a much better effect, shooting it maybe 10 yards.

I decided that a slightly different approach was needed. I have been playing with the idea of expanding foam rockets as an inexpensive, disposable missile system. I made a mould up from some plastic tubing…

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The three components: the body tube (top), nosecone former (bottom right) and the backcap (left). I have inserted the tail fins into slots at the top. I am yet to make a rocket from it yet however! I think that this will produce a more ballistically viable rocket that will also be cheap to reproduce if lost.

LAW M72 trigger mechanism

Anti-Tank, Cold War, Custom builds, LAW, Products, War on Terror

Video giving a behind-the-scenes view of a bit of R&D at Vintage Airsoft. Although it doesn’t look much yet, a far more polished version of this unit will feature in a custom-built LAW M72A7. Apologies in advance for referring to it as ‘L72’ in the video repeatedly!

LAW M72A7

Anti-Tank, Cold War, Custom builds, Era, LAW, Products, War on Terror

I received an email at the end of last year asking if I would be interested in building an M72A7. This is one of the latest incarnations of a real classic in the world of rocket propelled weapons with its origins prior to the Vietnam War where it first saw service.

M72A2

The concept of the M72 series (also known as the LAW66 in some parts of the world) of rocket launches was to produce a lightweight, single-use anti armour weapon.  Anti-armour technology had come a long way since the beginning of the Second World War: At the beginning of this war tanks could only be dispatched using small direct-fire artillery pieces, though developments were made in the direction of anti-tank rifles (the Boys anti-tank rifle is a classic of the genre) these proved to be ineffective against the armour of newer tanks and were incredibly heavy and cumbersome to carry.

The US introduced the Bazooka to Europe, the first really practical man-portable anti-tank weapon. It was actually so effective that the Germans pretty well copied it when developing their Panzerschrecks. The Germans also developed the Panzerfaust,  a single-use recoilless rifle  that also proved effective against tanks and popular with users.

Sub-calibre training version in the deployed position. Smaller rockets that are designed to replicate the flight path of the real deal are used for training purposes.

Being a single use weapon, the LAW’s rocket is an integral part of the system a soldier has to carry. Many of the improvements and upgrades to the LAW66 are of the warhead or the motor component of the rocket itself, though there are a number of visual differences from the outside including different sights, end caps and sight housings.

The LAW M72A7 features an improved rocket motor to engage targets past 200m and a picatinny rail for night-sights and laser pointers (though who would stick an expensive night sight on a disposable launcher I don’t now, nor what use a laser would be in all honesty, answers on a post-card please!)*.

Another view of a modern M72, in this shot the picatinny rail is clearly visible.

The Airsoft version of this will not, of course have a range of over 200m and this is a very experimental build for me: I have never done anything like this before! Designs sketched out, my first step was to test the trigger mechanism. Once my theory has been tested, I can build it into the end product. More to follow on that later this week!

 

*ANSWER: My client for this build gave me a bit of insight into the use of a picatinny rail and what it was for:

“Bit of trivia RE the night sight rail, if I’m not mistaken it is for a PEQ (Infrared light and laser) box so that soldiers using night vision goggles can aim it because the goggles would prevent getting a proper cheek weld to the weapon, and also the dark would render Iron sights unusable. They’re not so much the throwaway weapons they were in the Nam era as the Americans started to learn the enemy would use them as parts of IED’s by filling them with hand grenades. As a result it is standing operating procedure to retain the spent case and take it back to base with you for disposal or to crush/render useless the tube in which case they would take the PEQ off and probably put it onto the rails of their rifle.”

M72 with PEQ box.