Four Fun Facts about the Oerlikon 20mm Antiaircraft Cannon! 

Seems to be missing a large part of the base, namely a pre 1990 Toyota pickup truck.

This will be ideal. The drones around the neighborhood have become quite the pest lately.

"In the next video, I will be doing another fun facts series on the M777 Howitzer being sold here at the auction. If you are in need of a large artillery piece in your backyard instead of that in-ground pool your wife really wants, this is the ideal way to go."

It was one of these weapons Edward “Teddy” Sheean used to earn an extremely overdue posthumous Victoria Cross in 2020 for his bravery in WWII onboard HMAS Armidale by shooting down one Japanese aircraft and damaging at least 2 more while injured. His shipmates had already abandoned their sinking ship and were being strafed by the Japanese, and it was reported he was still firing as he slipped beneath the waves. He is now the only member of the Royal Australian Navy to have earned a VC, and the only junior sailor in the RAN to have a major combatant named after him, the Collins class submarine HMAS Sheean.

My dad was a gunners mate on board USS Amsterdam CL - 101. His duty station was one of these. He told me they couldn't hit the broad side of a barn with them. They just threw a wall of HE into the air and if the planes flew into it good. And many times they did just that. But that was his job. Stand behind one of those and pull the trigger.

Wow, the recoil spring itself is so strong that you could shoot a lethal crossbow bolt with it! There were military crossbows which weren't this strong!

So when do the main battleship guns go up for auction?

When I'm out hunting in Finland, I always shoot the ice off my Lahti before striking down an elk with a high explosive round. Nothing to see there... Seriously that whole shooting the ice off the muzzle thing and cocking the gun with a cocking rope is so incredible. Love the attidue of the guys who came up with this!!!

A Swiss gun that isn't massively overengineered, to the delight of gun mechanics around the globe.

Next video: one of Yamato's 460 mm turrets!

The cocking rope is also the sling.

On the cocking: You missed option 4: 3 strong men and a rope. (Not kidding; AIUI, that was one of the official procedures if you were in a hurry and the elevation cocking wasn't an option.)

Underway the 396lb of resistance would officially make it a 2 marine job (a private to shoulder the rope and an NCO to motivate them) yes?

My Grandfather was a skipper for a mine-sweeper with a few of these on it during WW2 and they had a near tragedy with the muzzle cap because not only did someone forget to remove it, the magazine actually didn't have the inert rounds in it. However, the HE round didn't actually explode passing through the cap because its fuse was faulty, so it managed to get a few hundred meters before finally half-exploding. Once in a while, things go so wrong that the worst wrong is cancelled out in the process...

"... or, if you just happen to be an idiot ..." Ian, your videos are the absolute best!

Do you recomend it for consealed carry ?

Many years ago I came across a stash of old "Guns & Ammo" magazines from the early fifties. There were adds in the back selling these things as military surplus to the general public. I can't remember the price but I remember thinking "wow, that's pretty affordable!", and I was 10 years old.

The bolt-bone is connected to the action-arm bones, the action-arm bones are connected to the sleeve bone. The sleeve bone is connected to the recoil spring bone.

Thanks for the great video! I just finished re-reading Alistair MacLean's excellent WWII naval battle classic "HMS Ulysses". The book vividly describes the Arctic convoy runs from Iceland to Murmansk and this gun shows up many times as the heavy cruiser tries to ward off German bombers and dive bombers. One of the gunners does, indeed, blow up his gun by firing an HE round with the cover iced up. Reading that book gives one a whole renewed sense of respect and even awe at the men in the British and American Navies and the men who served as Merchant Mariners.

I served 11 years in the Royal Navy and one of the ships I was on was a minesweeper in the Persian Gulf and this ‘sweeper had a double barrelled Oerlikon mounted just abaft the funnel. The firing position for the aimer was on the left of the mounting with both guns on his right-hand side. One day when the squadron was at sea it was decided that a practise shoot was needed, the first time the Oerlikon had been fired since I'd been onboard. One of the ‘sweepers towed a splash target and as it passed, the other ‘sweepers steaming line astern opened fire on the target as it came to bear. Our gunner opened up on the target and the left gun jammed, the gunner looked over his right shoulder at the gun saw that the next shell in the magazine, which was a tracer, had somehow been activated and was burning in the magazine. He calmly unshipped the magazine and threw the whole thing overboard before any more rounds in the magazine caught fire. The he threw that magazine a distance of about 15ft, straight over the side, which was a fair feat of strength because those magazine are not light when they are empty but full of rounds they are weighty piece of kit..

I can just picture Matt from Demo Ranch buying this... lol "Don't tell Mere. SERIOUSLY DON'T."

The Oerlikon management must have worn mourning bands for 6 months after peace was signed in 1945.

Four years late but I yelled out loud "COOL" at that cocking mechanism.

Estimated Price: $25,000 - $40,000 I would have thought higher

Funny that Ian mentioned the "...free space in your living room..." Back in the late 1980's, I knew a guy who had a de-activated Oerklikon in his living room; mount and all. Damn, it was so cool.

Just informed the missus that I'm off to auction to buy a 20mm anti-aircraft gun. She informed me that if I go to auction again, she goes for good... On the bright side, at least now I have enough space in the living room for my new Oerlikon!

Would you recommend it for home defense?

Alright... Now I want to see Ian do a mag dump on this gun! 😁👍

Cue "That's not a gun...THIS is a gun." in an Australian accent.

30 seconds to change the barrel and we didn't even get hand motions to describe the procedure? 8.5/10

Cool video, Ian. I knew everyone used these but your other 3 facts are new to me. The bit about loading solid shot at the top of magazines to clear ice is a bit mind-boggling.

Had these on the Viet Nam PTFs. 1 each on port and starboard. I was a loader on my first PTF and the snail mags were really heavy for a skinny 20 year old. The big risk was a hang fire - if it blew it would take the whole mount (and crew) out - unscrew and throw over the side. If you were lucky.

Does your new display wall have a hook for this one?

The 20mm was effective in US Navy service until the Japanese resorted to Kamikaze tactics late in the war. It could not stop Japanese aircraft on a crash course. Navy personnel above decks knew "When the 20mm kicks in, that's when it's time to hit the deck," and crew members below decks knew it was time to close off the air intakes to avoid the fire from the Kamikaze strike from being drawn into them. Even the 40mm Bofors guns had a hard time stopping the Kamikazes. They were replaced by a 3-inch AA gun shortly after the war, and the 20mm was removed entirely. Still, a great weapon up to 1945.

Excellent video, learned all about the Oerlikon back in the 1970's from "Boats" Newberry at the PT Boat museum, fascinating gun.

I used to work on a Oerlikon. It was a horizontal borer we used to machine the mine hunter HMAS Huon exhaust manifolds for re-sleeving. Was old but worked well.

Anyone with a yacht a that wants to sail all over the world needs one of these especially if they are planning to sail around Africa.

Oerlikon cannon! And Ian! And.... DAKKA DAKKA DAKKA DAKKA

Holy crap that makes so much sense as to why you always see these things pointing straight up in vintage pics. I always thought it was to get the barrels out of the way but the cocking system explains it way better. Thanks.

What a treat this video is. Thanks Ian!

Funfact nr. 1 is: this is legal not a weapon in switzeland! I know a guy who owns such a thing.

"or if you just happen to be an idiot" sounds like my kind of gun

Thank for you posting this video. My father was a GM3 on the S.S. George W. Childs and was primarily assigned to the 20MM Oerlikon. He was aboard the Childs at the Normandy invasion. The Childs was deliberately sunk in the sand as part of the artificial breakwater for Mulberry A. My father and the rest of the crew were aboard the ship for two weeks before heading back to England. He's 92 and still sharp. I asked him about the manual for the Oerlikon. He says that he never saw one. He was trained at the Brooklyn Armed Guard Center. Armed Guard crews were pretty much on their own after that. He was aware that if a shell got caught in the breech, he had about a minute to clear it before it would explode. Fortunately, that never happened. Thanks again for the video. My father will enjoy seeing this!

Thanks for the excellent video! My father used to fire just the same gun - he was in The Royal Navy on a HDML and saw action on D-Day...

Ian you NEED to do more vids about aircraft guns if you get the chance. Even if man of them are rather know, or obscure at best. It's hard to find some nice footage of those. I'd love to hear some more about those electrically primed M3 .50s or German MK103s.

"Oh that's just a keyfob, Officer." Finally something useful to put in the back of my Ford F-650. Texas Technical.

That weapon was a gamechanger for light naval AAA ,setting the standard for most of the war. By 1944 however the 20mm Oerlikon was considered to be too light to deal with air threats (particularily so Kamikazes), and more emphasis was put in the Bofors as the baseline for light naval AAA defence. When are you going to get the chance to do a video about that one? ;). And...that's some amazing job you have Ian, will never stop repeating it. I'm just drooling each time you put up something like this :).

Fascinating stuff as always ian

Wish you could have demonstrated it, though...

Someone needs to let Burt Gummer know when the next one goes up for auction.

loved the outro. full of wit and witticism

Ian, I enjoy all your videos and your slightly restrained sense of humor... terrific reporting and of course, generally all that great research you put into your work. Please keep it up. (ex army competition shooter)

Finally, a gun I can use to protect my vegetable garden from them squirrels and rabbits!

This is the gun that the Swiss wanted Charlie Wilson to arm the Afghans with to fight the Russians... They tried to convince him that it was mule portable...

Thanks for an interesting overview. The widespread success of the design speaks for itself.

Brilliant! I worked at a museum with one (old german one) and this really gave some background. Good on ya mate!

Lol modern gun with medieval crossbow cocking system. Yes, the gun would look cool on my new torpedo boat. 😂

That would go nicely on my porch. "GET OFF MY LAWN!"

These facts cranked me up so damn bad man

the cocking arrangement is brilliant.

The perfect answer for dealing with your neighbor's pesky drone fly overs.

Is the Mjolnir armor and Warthog sold separately, or is a package deal available?

The model we used had cocking arms attached to the base. You would domp the gun and attach those arms to the lugs on the front side of the action-arms; then you would use your body-weight to raise the muzzle and while doing this the cocking arms would pull the action-arms back and cock the cannon. Extra fact: the last rounds out of a magazine need to be shot as a burst; if you try to single-shot these rounds, the spring in the magazine wasn't powerful enough to feed the cannon when said cannon was going up, down and rolling left to right on a moving ship.

Once again Ian...a great video...

Will you make "final auction prices" episode for this piece?

Fun fact Nr. 5: The other most important AA gun of WWII, the Bofors 40 mm, also came from a neutral state. ;) What do we learn? Defensive oriented neutral states obviously design the best defensive weapon systems. Though I have to admit, coastal defense weapons are not really a concern for Switzerland.

I would seriously love to see a full review of this gun!

💪 vid, as always. Thanks for all the quality (entertaining) information. Take care & be well!

Gonna take this on my cruise through Somalia.

This weapon was the base design for almost all 20mm cannon in WW2

Hey Ian, I like that you're starting to use more video editing techniques. It's great to watch this channel grow in production value.

Fun fact: In 1969 US Army, AIT 11Delta Armor Recon school, Ft Knox Kentucky, we were trained in the use of a 20mm cannon mounted on our APCs! It had a driver-controlled switch box with single, 3-shot burst, and full auto positions. The TC in the cupola aimed and ordered the shot sequence which the driver set and pulled the trigger! It was a fun weapon to play with but I didn't see any mounted on APCs in Vietnam.

glock mags?

...they can sell that? Holy crap.

i like it when ian uses his sarcasm for good . very entertaining

There's two PT boats out there-fully operational, that I know of on the water. PT 658 in Portland, OR and PT 305 in New Orleans. Both are fully restored Higgins PTboats and are on the water.

I was completely mispronouncing "Oerlikon" until now. :)

DO A BOFORS!

Thanks, Ian. I'm an armchair historian with particular interest in the weapons of the WW2 era. Oerlikon, and its descendant, the Polsten, figure heavily in accounts. It's nice to understand operation of such a weapon, but revealing its oddities and flaws tell us so much more about arms design and the evolution of weapons systems. Additionally, as a writer, knowing the quirks helps me both delight and better inform my reader base.

Awesome! You definately deserve more subscribers!

One of these mounted on each bridge wing would give "pirates" something to think about when merchant ships close Somilia.

Imagine bolting that down on the back of your pickup truck :)

Excellent , as usual !

Awesome video with cool facts.

Y'know, when we Europeans go "So, uh, you're from the US...?", this is the kind of thing that springs to mind for us... xD

You know, I need this, for reasons. Pretty sure I'll come up with reasons, I know I have reasons, just not sure what those reasons are yet.

I’ve got a pair of mk4 oerlikon casings from 1944! Nice to see this video pop up

Great show!

I've got too much free space in my living room, I think I need some self-defense against intruders... 1000 yards away (914m).... in airplanes... I live near an airport. I'm sure the Durham Region Police and the Mounties won't mind a Canadian owning a 20mm auto-cannon for self-defense. Might come in use one day :)

Wait... They are selling a f***** AA-Gun? That's what I call serious business ;)

Thanks Ian, some interesting information i can put to use on my Oerlikon !

Wow. Four important points suitable for potential illustrators, novelists, and comic artists to freshen the popular perspective. Nice stuff, Ian.

The Luftwaffe used this in aircraft as the MG FF, most famously on the wing mounts for the 109E but in a few turret installations when they realized they needed heavier bomber defense but the MG-151/20 wasn't ready yet (pretty sure some of the early model FW-200s had them in a ventral turret). I wonder how they dealt with the cocking issue in either case--hydraulic pressure?

4 facts, eight minutes? legit info.

I live right next to the USS Alabama and she is absolutely BRISTLING with these things in single and double mounts.

You're such a great story teller!

Both a machine gun and a "destructive device", being .80 caliber, no? I think I've found a new home defense gun.

Hey question for Ian or anyone that can answer. Is there a rifle or firearm that is open bolt, but does not have a bolt carrier (thus just has the bolt contained by the receiver). But also is lock breaching and operated through a gas piston. Because i can't think of one that has such a set up, but at the same time i highly doubt i came up with a new set up.

Another great video Ian! I wonder has that type of operating system been used anywhere else? Also was surprised to see how thin the barrel walls look.

Number One is a two-fer. Thank you Ian for the added value.