Artillery experiment or heavily armed aircraft

[CAPILATUS]

Hi to all,
Once going through the source it pushed me to one thought. Nomally when we compare any plane we rest upon aircraft were serially built. But as you know it was numerous of experimental aircraft produced.

In this nomination please, point any aircraft [u]ever flown</u> since 1940 till 1945, and please consider only artillery. Bomb load, rockets or ever might be incloded in normal payload of the aircraft, but it's not the topic.

All we need just artillery for attack purposes, to attack plane, troops - doesn't matter.
Here we go, gentlemen... GIVE ME MORE GUNS!!! [}:)][}:)][}:)]

[BuzzLightyear]

Ummmm, ok.

Beechcraft XA-38 Grizzly
http://www.wpafb.af.mil/museum/research/attack/a5/xa38-10.jpg

SPECIFICATIONS
Span: 67.08 ft.
Length: 51.7 ft.
Height: 15 ft. 6 in.
Weight: 36,332 lbs. maximum alternate gross weight
Armament: Six .50-cal. machine guns (two fixed in the lower forward nose and two pairs in General Electric remote-controlled dorsal and ventral turrets); one 75 mm cannon plus a variety of external stores including bombs, fuel tanks, smoke screen chemical tanks, torpedoes and depth charges
Engines: Two Wright GR-3350-43 "Cyclone" radials of 2,300 hp. each
Crew: Two - Pilot and Gunner


PERFORMANCE
Maximum speed: 370 mph. at 17,000 ft.
Cruising speed: 350 mph. at 16,000 ft.
Range: 1,625 miles
Service Ceiling: 29,000 ft.

[GregP]

If I am not mistaken, the war closed with the most heavily armed aircraft being the Sukhoi Su-7 (maybe Su-8? ... one of the two ... a twin engine piston aircraft like the Pe-2 / Tu-2 genere). It had absoultely amazing armament.

I'll look it up and repost when I find it, but it was something like 8 machine guns, plus 2 x 20 or 23 mm cannon plus 1 x 37 mm cannon plus 1 x 75 mm cannon. One burst would deactivate/destroy almost any target.

Not great performance, but it doesn't HAVE to be when one shot is a kill, and it WAS.

Correct me if I am wrong; I am away from my normal computer right now ... and do not have any reference access. The past has revealed my memory to be less than stellar ... though right on the salient points.

[Romantic Technofreak]

O.K. I try to make a quick list without very good subtype mentioning.

Bell P-39 "Airacobra" and P-63 "Kingcobra" fighters with single 37 mm propeller-mounted gun.

Fiat CANSA F.C. 20 ground attacker prototype with 37 mm.

Henschel Hs 129 ground attacker with 37 mm. Trials with 75 mm had been made on the frontier because of the already desperate antitank-defense situation. Plane failed because of the unsuited engines for dry-sandy climate like in North Africa or Ukraine.

Junkers Ju 87 well known tank destroyer with 2 x 37 mm.

Junkers Ju 88 P-1 with 1 x 75 mm. Not successfull because "gun powder gas caused propeller blade tip vibrations". P-2 with 2 x 37 mm, successfull.

North American B-25 version with 7,5 mm. Very successfull shipping scourge. Gun very unattractively hidden in the nose. A game site said (sorry not being able to find it again) "Flight characteristics like an overloaded pig"!:D

Mitsubishi Ki-109 derivation of Ki-67 bomber with 75 mm designed as B-29 hunter, not successfull. Had better been used as ship scourge like the B-25.

Piaggio Pi-108 "Artigliere" single prototype with 105 mm gun. Probably the heaviest armed that flew during WWII. Not successfull, because already single shots shook all screws and nearly blew the surface away.

Me 262 and Me 410 bomber hunter versions with 50 mm gun.

Prototypes Lockheed XP-58 "Chain Lightning" and McDonnel XP-67 "Bat" with 4 or 6 x 37 mm guns.

Sukhoi ground attacker prototypes Su-6 and Su-8 of course. See more on my contribution at the "Best ground attacker" thread where I added a list of "obscure" airplanes that could have been best, but had not had the chance.

A version of the Junkers Ju 288 with a recoilless 280 mm gun was constructed (took the whole lower fuselage of the plane and pointed a huge barrel in front). The plan was not executed before the end of the war.

Yours sincerely, Romantic Gunsmith.

[Romantic Technofreak]

Looks like or well-scorned Savoia S.M. 85 had a well-armed cousin, the S.M. 89:

http://www.finn.it/regia/immagini/savoia/sm89.jpg

No other information was found, even "Gustin" does not know about it. There surely was no use made of it, favourably (for its crews;)).

[Corsarius]

You forgot the Heinkel He-177 ground attack beastie with it's 75mm tank buster.

[CAPILATUS]

Yeees!
As mentioned above with some of you, gentlemen, I nominate...
sure, Su-8 super heavy ground attacker.

It was about to go to series, but there was an engine's problem with M-71F same reason why the fighter I-185 was be serial.

Well.
year of production 1943

armament firing forward:
four (!) 45mm cannons NS-45
four 7,62 guns SHKAS

Making calculation we have 21,2 kg/sec fire velocity!
Damn, it's too much!

And, please, note it had 1680kg of armo!

Speed - 550km/h
Range - 600km

http://www.airwar.ru/enc/aww2/su8.html you can see the picture here, as I still don't know hoe to put in...

Any competitors?

[Romantic Technofreak]

No, Capilatus, I think the Su-8 had the hardest punch of all airplanes flown in WWII. Although having to repeat myself, for people who don´t speak Russian I again insert a link about the Su-8:

http://worldatwar.net/chandelle/v3/v3n2/su-8.html

Corsarius, I honestly don´t know about a He 177 ground attacker version. What I know about are two things:

1. A long-distance destroyer project with 2 x 30 mm MK 101, designed to catch Allied bombers on their transfer flight to Britain over the Atlantic. But this was much too slow.

2. Having experienced the Allied mass-bombing after the Normandy invasion, Göring ordered the He 177 units on the Eastern frontier to low-level attacks against the Russian Belarus offensive in Summer 1944. The units were nearly erased, of course.

[CAPILATUS]

Damn!!! There is a competitor!
Just found Hs.129b-3/Wà equipped with two 75mm BK7.5

Romantic Technofreak, dear comrade, can you calculate velocity? As I can't find BK7.5 and it's shell's characteristic.

[simon]

The BK7,5 was I understand the Luftwaffe's name for the PAK-40, although there may have been minor differences if you use the statistics for the latter you probably wont be far wrong.

The ground attack He177 was I think the He177P, and was armed with a jetisonable BK7,5, apparently only used over the eastern front. Will dig out more references if I can find them.

[Romantic Technofreak]

Damn!!! There is a competitor!

I am not convinced, dear friend.

Just found Hs.129b-3/Wà equipped with two 75mm BK7.5

Only ONE! These toys are damned heavy. Look the statement I quoted about the B-25 above!

Romantic Technofreak, dear comrade, can you calculate velocity?

Muzzle velocity is 790 m/sec.

As I can't find BK7.5 and it's shell's characteristic.

Weight 705 kg. Able to fire 30 rounds/min. Developped from the Pak 43.

Besides this, the Hs 129 was not equipped with high-performance engines, and even these were unsuitable for sorties in a dusty environment, and it also had no rear defensive armament. So if you really want to enjoy the fireworks, you must choose the Su-8!

[Ricky]

Romantic Technofreak -

I can't believe you forgot the Hawker Hurricane Mk.11d in your list -
a tank-buster with 2x 40mm cannon

[simon]

Also known as the Hurricane MkIV, basically the same aircraft... ;)

Wasn't there also a ship / U-boat killer mossie version with a nice big cannon in the nose?

[CAPILATUS]

Romantic Technofreak,

There were [u]exactly two </u>BK7.5 (PAK40 or PAK40L)
and with a rate [u]40 </u>round/min

About 24 were produced and took a part in combat 17 planes in 10 and 14./SG.9 squadron.

What I need, just a weight of a shell, to calculate fire velocity per sec.

I have the figure 11,8 kg but don't know if it was the weight of cartridge or a shell.

Could show you the links but all of them in Russian.

[Ricky]

I too have a memory of a big-gun Mossie, for ship-killing.
Admittedly that memory is curtesy of an Airfix kit...

I *think* that it was 50mm (maybe 75?) and was for use in the Pacific (the kit for that model was in RAAF colours).

I welcome all your corrections!
;)

[Romantic Technofreak]

Capilatus, it WAS only ONE. Your sources must contain a mistake, even the version with BK 3,7 carried only one. Remember the Hs 129 is SMALL and this gun is BIG. If you still don´t believe me, I got some pictures in these links:

http://www.warbirdsresourcegroup.org/LRG/hs129.html

(scroll down here for close-up view)
http://www.worldhistory.com/wiki/H/Henschel-Hs-129.htm

You see the size relation between airplane and gun, you see it is only one, and you see this small aircraft could not carry more, its flight characteristics were already bad enough. Total shell weight was 6,9 kg.

Ricky, you are right. Not to mention the Hurricane "tincan opener" is an unforgivable failing. And what is more: I also forgot the other double-40mm-fighter, a version of the Nakajima Ki-44 Shoki. There even were some more Japanese designs carrying 37mm guns. Last for here, but maybe not at all, I also just remembered the Fiat AS 14 prototype, a land derivation of the RS 14 float reconnoisater, carrying a 37mm or a 45mm gun.

[CAPILATUS]

H-mmmm! To think logicaly you are right, dear Romantic Technofreak!
I was surprised as well! Keep trying to find the English source saying same...

[Romantic Technofreak]

What we are doing here is something I call semi-historian work. I love to study history but I have to admit that I did not want to spend my life in dusty archives. So I also must believe the most things I read, but by getting more and more informations, some of them contradictory, and discussions like these we sometimes can bring the truth to daylight, like the fairy tale about six Mosquitoes shot down shortly after the first successful flight of the Heinkel He 219!

[tenmmike]

the hs-129 was fitted with the (1ea) BK7.5 and did see VERY limited action..i have pictures of hs129c-1/v4 and was standard on the hs 129b-3/wa...............BK7.5...MV approx 700m/s projectile weight 6.8 kg......it should be noted that the BK7.5 pack could be jettisoned in a emergancy........ROF 40 rpm ....it did see combat with these units 10 and 14(pz).SG 9.. and did well although primarily to kill soviet tanks that had broken thru the lines..the little plane was quite burdend with it though...NOTE..the bk7.5 used a slightly under powered version of the normal pak 40 roud that had 790/ms vel and 2,120k joules......but a majorty of that was made up by adding airspeed to M/V

[tenmmike]

bump

[GregP]

I wonder how many cannon shots the HS-129 could take before the ariframe was scrap metal?

The American B-25 Mitchell could shoot somewhere between 15 and 20 shots before the plane was scrapped.

I worked with an old boy whose WWII nickname was "Pappy Gunn" and he worked and flew on the B-25's that carried the 75 mm gun. He stated that the only birds converted to this configuration were old, war-weary workhorses due for retirement because after 15 or 20 shots, the rivet holes were egg-shaped and the plane was literally falling apart. In these old B-25s, the gun was hard-mounted to the airframe and there was no recoil absorption to speak of, so the entire shock of firing the weapon was transmitted directly to the airframe.

He stated that one shot would result in the aircraft losing about 10 or 15 knots of airspeed, and the whole crew was reeling from the shock ... so passes with multiple shots were a thing to dread, and were dangerous since you would lose a LOT of airspeed just when the ship's antiaircraft gus were closest to the B-25.

I wonder about the recoil absorption characteristics of the Henschel and the Sukhoi ... anyone know anything about it from personal accounts or general knowledge of the particular variants?

[Corsarius]

To my knowledge, the idea for the 'big gun' B-25 CAME from "pappy" gunn, so I don't know why he didn't seem so keen on it later.

Also, to my knowledge (might have to do some research here) the PAK-40 had some sort of suppression system and was not hard-mounted to the airframe. In fact, it was in a droppable pod in a similar manner to the AC-123 aircraft of Viet Nam vintage which would dump EVERYTHING if they got in trouble so they could get home.

[tenmmike]

quote:Originally posted by GregP



The American B-25 Mitchell could shoot somewhere between 15 and 20 shots before the plane was scrapped.

I worked with an old boy whose WWII nickname was "Papopy Gunn" and he worked and flew on the B-25's taht carried the 75 mm gun. He stated taht the only birds converted to this configuration were old, war-waery workhorses due for retirement becuase after 15 or 20 shots, the rivet holes were egg-shaped and the palne was literally falling apart. In these old B-25s, the gun was hard-mounted to the airframe and there was no recoil absorption to speak of, so the entire shock of firing the weapon was transmitted directly to the airframe.

He stated that one shot would result in the aircraft losing about 10 ro 15 knots of airspeed, and the whole crew was reeling from the shock ... so passes with multiple shots were a thing to dread, and were dangerous since you would lose a LOT of airspeed just when the ship's aitiaircraft gus were closest to the B-25.


i belive that is incorrect as the G (equipped with the m-4 gun)and carried 21 rds as its load and H (with the lighter m-5 initialy known as the t13e1)these modeles came from the factory with the .75 mm mounted////// Colonel Paul Gunn of the US Fifth Air Force in Australia, had experimented with the installation of a 20 mm cannon in the nose of a B-25. Colonel Gunn, abetted by a North American Aviation Company Tech Rep named Jack Fox, sent the idea to North American in Inglewood, California where it was promptly taken a step further and worked into the installation of the 75 mm cannon. General George Kenney came up with the ideas and "Pappy" Gunn put the ideas to work.
It required a crewman to load, fire and extract the casing. And when it fired it felt like the aircraft had "hit a brick wall", but with its 2.95 inch (75 mm) projectile, it could turn a tank into scrap metal and punch very large holes in Japanese destroyers and barges at a range of nearly 2 miles. The Japanese paid dearly for the ideas of Kenney and the ingenuity of Gunn/////////////this i provide from 3 seperate sources (2 book and 1 web)

[GregP]

Both of you are correct.

I never said pappy wasn't "keen" on the idea. I said that the conversions were mostly, if not all, older B-25s that had seen a lot of service, and that only a few shots could be fired before the plane was literally falling apart.

I have no first-hand knowledge of the recoil system, if there was one ... only an account from someone who flew them and helped invent them.

He never said there wasn't a recoil system. He said the planes were ready to fall apart on their own after only a few shots were fired ... maybe 15 - 20 shots or so, and so it was a good thing they didn't spot a large number of targets.

[tenmmike]

the 75 mm in the b-25 recoiled 53 cm.... i cant find recoil info on the bk7.5 other then the fact the case length of the bk7.5 is consideraly longer the m-4's therefore the recoil must be substantualy more............yes i know the m4 was manual load

[simon]

Perhaps GregP's sources are refering to a slightly different aircraft? His references seem to refer to old worn out airframes being converted whereas Tenmike's seem to show factory fresh new aircraft intentionally mounted, to build a brand new aircraft that was only going to be able to fire maybe 2 dozen shots would seem extravagently expensive.

I'd suggest, and I'm doing so without any evidence our sources to back this up, merely that this seems a logical explantion, that around the time or just before the new aircraft were being rolled out of the factory, complete with recoil absorbing mechanisms, perhaps field units were also retrofitting almost life expired airframes in the field and fixing the cannon to the airframe without any recoil absorbing mechanisms. This would account for the differences between the two accounts, and also for what would otherwise seem a hugely wasteful practice.

Anyone know if this may have been the case?

[GregP]

Hey simon and tenmike,

The account I heard concerned conversion in the field out in the Pacific theater. Factory fresh B-25's with the 75 mm cannon were never mentioned. A new airpolane with an expected service life of 20 shots DOES seem extravagant, doesn;t it? Even for wartime expediency.

So ... I'm with simon. The likely explanation is that the factory planes had a recoil system while the field conversions didn't, though that is obviously a guess on my part. I have nothing to base it on and no opportunity to check it out.

Last, the discussion happened at a time when the WWII was decades old. Memories get selective after that length of time. Perhaps there was some "embellishment" that was unintentional, can't say. I only listened. With no point of reference, I certainly couldn't discuss or argue any points.

[PMN1]

quote:Originally posted by Ricky

I too have a memory of a big-gun Mossie, for ship-killing.
Admittedly that memory is curtesy of an Airfix kit...

I *think* that it was 50mm (maybe 75?) and was for use in the Pacific (the kit for that model was in RAAF colours).

I welcome all your corrections!
;)


FB. Mk XVIII Mosquitto aka TseTse with a 57mm mollins cannon for use against U-boatd though a Ju88 did have the misfortune to fly into the pasth of one and paid for it - see the link below


http://www.quarry.nildram.co.uk/Molins.htm

[Romantic Technofreak]

My books say nothing about a recoil-damping system for the BK 7,5, but the second link I placed does: A huge hydraulic system was used to damp the recoil of the gun, .
So it looks like the Hs 129 was grounded by engine failure before it was unscrewed by gun recoil:([8D]!
By the way, can somebody tell something about the effect of expanding gun powder gas, especially on propeller blades (happened to the Ju 88 P-1)?

[Ricky]

In Greg's Link (http://win.www.airwar.ru/other/drawe.html), picture 9 on the Bristol Blenhiem series (http://win.www.airwar.ru/other/draw/blenh1.html)
shows what appears to be a Blenhiem IV armed with 8 underwing rockets, 6 rifle-caliber machine guns in various blister packs, one .50 cal machine gun and a larger gun (up to 50mm?) in the nose. plus, of course, the mid-upper turret.
Obviously, (as far as I know) this was not an operational Blenhiem, but does anyone have any further information on this project?
There is a description written on the page, but I can't read (or speak!) Russian.
Capitalus, could you help maybe?
:)

[MikeD]

There is mention of the Ju288 with a 280mm gun tested, yet some of the prototypes were used operationally with a 50mm gun, I believe a BK5 as used on the Me 410. Another aircraft that used a 37mm and a 45 mm in the propellor hub were two variants of the Yakolev Yak 9 again these were operational.

[Tony Williams]

Aha, a favourite topic of mine! I put a whole chapter on WW2 ground attack planes and their gun armament in 'Flying Guns – World War 2: Development of Aircraft Guns, Ammunition and Installations 1933-45', which I wrote with Emmanuel Gustin (details on my website!).

For a shorter summary, see: http://www.quarry.nildram.co.uk/tankbusters.htm

Tony Williams: Military gun and ammunition website (http://www.quarry.nildram.co.uk) and discussion
forum (http://forums.delphiforums.com/autogun/messages/)

[Ricky]

I have answered my own Blenhiem question - several Blenhiems were fitted with 20mm cannon in the nose to fulfil anti-tank duty - Basically we were getting desperate.
The Blenhiem with belly-pack of 4x.303 mgs had proved useful at straffing columns of lorries. However, the units issued with the 20mm cannon were not the same ones that had been trained in ground straffing, and furthermore thay had not been given any of the maintenance tools for the cannon! During practice flights crews felt lucky if they fired multiple shots before the gun jammed.
Luckily these lash-ups were never used.

[Tony Williams]

Do you have a reference for the Blenheim/Hispano? I know that the Lysander was fitted with two 20mm for anti-invasion duties, but I hadn't heard about the Blenheim.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk
Military gun and ammunition discussion forum: http://forums.delphiforums.com/autogun/messages/

[Ricky]

That was in the North African Campaign.
My reference was the official history of 45 Squadron (The Flying Camels) - it includes several pictures of Blenhiems with 20mm cannon fitted.
They were attached to the floor of the cockpit, with the barrel sticking out of the glazing in the nose - just like the example in the link provided earlier.

[Tony Williams]

Thanks!

TW

[CAPILATUS]

quote:Originally posted by Tony Williams

Aha, a favourite topic of mine! I put a whole chapter on WW2 ground attack planes and their gun armament in 'Flying Guns – World War 2: Development of Aircraft Guns, Ammunition and Installations 1933-45', which I wrote with Emmanuel Gustin (details on my website!).

For a shorter summary, see: http://www.quarry.nildram.co.uk/tankbusters.htm

Tony Williams: Military gun and ammunition

Mine as well! I like big guns! :D
Tony I started to read your article and think you did a mistake. All sources I have, saying VYA-23 (TKB-201) was NOT a scaled up gun from UB. It was independent construction made by different desingers, like it's competitor MP-6 (23mm). Ineresting fact VYA-23 was tasted in flight mounted on Me-110 in 1940 as IL-2 it developed for was not mass produced yet. The gun was installed in fuselage of Me-110. In data I have - said shell can penetrate 25mm/90 armor from 400m.

[Tony Williams]

You are right that the two guns had different designers; the VYa was by Volkov and Yartsev while the UB was by Berezin. I cannot now recall where I read that the VYa was a scaled-up UB. It does in fact use the same type of mechanism and looks very similar.

Tony Williams: Military gun and ammunition website (http://www.quarry.nildram.co.uk) and Discussion forum (http://forums.delphiforums.com/autogun/messages/)

[tenmmike]

[:0]Mr. Williams i am the proud owner of several of your books thanks for all your hard work.....to yall who do not know him he and DR Emmanuel Gustin are in my opinion the finest writers/ histotians on subjects such as this i cannot recommend his books more highly, please follow his links his books are supurb.

[Tony Williams]

Thanks for your comments, they've cheered me up this morning!

Drifting slightly off-topic, my latest book is an 'alternative WW2' novel, which needless to say contains a lot about aircraft, their armament (historical and fictional) and aerial combat. There's a brief summary on my website front page, and there's a link to the publisher's site where you can read the first chapter. It can be downloaded as an e-book now, or bought in paperback shortly.

Tony Williams: Military gun and ammunition website (http://www.quarry.nildram.co.uk) and Discussion forum (http://forums.delphiforums.com/autogun/messages/)

[CAPILATUS]

quote:Originally posted by tenmmike

[:0]Mr. Williams i am the proud owner of several of your books thanks for all your hard work.....to yall who do not know him he and DR Emmanuel Gustin are in my opinion the finest writers/ histotians on subjects such as this i cannot recommend his books more highly, please follow his links his books are supurb.
I'm happy for you, tenmmike, you have them. And I don't yell, I pass my well-reasoned opinion.

Tony, I don't think you could find at least in Russian sources saying VYa was scaled up from UB, no way. Might be you read about B-20, cannon was really scaled-up from UB, not VYa.

Tony, if this disputable argument is not important for you and your books - not a word from my side concerning this. If it's important I get started my own research since now to give you argumented explanation to this I find obvious. The matter I studied aviation cannons in high military school long time ago and hope to provide you with appropriate information you coud use in your books with a little hope at the end to get one of your books with your own autograph, i'll pay for this book.;)

Is it deal?

[Tony Williams]

quote:Originally posted by CAPILATUS
Tony, I don't think you could find at least in Russian sources saying VYa was scaled up from UB, no way. Might be you read about B-20, cannon was really scaled-up from UB, not VYa.

Tony, if this disputable argument is not important for you and your books - not a word from my side concerning this. If it's important I get started my own research since now to give you argumented explanation to this I find obvious. The matter I studied aviation cannons in high military school long time ago and hope to provide you with appropriate information you coud use in your books with a little hope at the end to get one of your books with your own autograph, i'll pay for this book.;)

Is it deal?


I'm ALWAYS interested in learning about this subject, particularly since there is so much mistaken information around. So I never absolutely believe anything I read, unless it is backed by hard evidence; I have even known primary sources to contain mistakes, and eye-witnesses to get things wrong. So yes, I would be interested in any reliable sources of new information.

Incidentally, the B-20 wasn't exactly scaled-up from the UB - it was just rechambered for the ammo. The 12.7x108 and 20x99R rounds were much the same size. You can tell from this photo of rounds from my collection; it is attached to the article on my site on WW2 Fighter Armament Effectiveness.
http://www.quarry.nildram.co.uk/WW2aircart1.jpg

P.S. The main problem with sending books abroad is payment; currency conversion costs plus postage often end up costing more than the price of the book!

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk
Military gun and ammunition discussion forum: http://forums.delphiforums.com/autogun/messages/

[CAPILATUS]

quote:Originally posted by Tony Williams
Incidentally, the B-20 wasn't exactly scaled-up from the UB - it was just rechambered for the ammo. The 12.7x108 and 20x99R rounds were much the same size. You can tell from this photo of rounds from my collection
Good collection you have, Tony!

Let me first compare ShVAK (12,7mm) and ShVAK (20mm). Why ShVAKs? I still can't find good info with pics about B-20, but I keep looking. The matter machine guns 12,7mm UB and ShVAK used same cartrige. So we could draw parallels, as UB and B-20 used same way!
Weight of cannon and machine gun ShVAK's was same - about 40kg. The different was only in barrel for 20mm shell, you can just look at the picture and could see the case for shell 20mm and bullet 12,7mm is same, just adopted for 20mm shell. Then please, have a look at 23mm shell VYa. Much bigger case isn't it?
http://forum.sukhoi.ru/attachment.php?attachmentid=32932

Yes, the shape of cartrige for 12,7mm, 23mm, 37mm looks similar, and autofire principle could be similar, but it does not mean NS-37 was scaled up from UB.
Pics of UB 12,7mm and VYa cannon 23mm (I havn't got a photo of B-20 yet)
http://forum.sukhoi.ru/attachment.php?attachmentid=32929
http://forum.sukhoi.ru/attachment.php?attachmentid=32931

Weight of UB-21kg, B-20 - about 25kg
Weight of VYa cannon - 66(!)kg. Don't you seem, dear Tony, it's strange? The difference in caliber only 3mm so great difference in weight of the guns? The answer is simple - VYa-23 was being developed in independant way for new came more powerful cartrige. The weight of the shell (200gm) two times bigger then for ShVAK 20mm cannon! Therefore whole developed mechanism should experience huge stress, much higher then ShVAK or B-20 cannons to provide appropriate fire rate and ballistic of the havy shell.

quote:P.S. The main problem with sending books abroad is payment; currency conversion costs plus postage often end up costing more than the price of the book!
It's not a problem as I'm moving over soon to Canada ;)

With respect.
CAPILATUS

[CAPILATUS]

Goddamn!
I tried to attached some pics but failed. Seems I did right.

Tony, I sent to your mail [email protected]
the same pics, could you attached 'em here, please?

[Tony Williams]

Hi,

Thanks for the pictures. I suspect that they have to be put on a website before they can be posted.

Strictly speaking the ammunition for the 12.7mm ShVAK was not the same as that for the UB - it had a rimmed case, and the 20x99R was in fact made by increasing to neck size to take a 20mm shell. However, it was about the same size.

I know that the 23x152B Vya cartridge was larger than the 12.7x108 - I have one of those in my collection too - which is why I said the VYa was 'scaled up from' the UB, i.e. bigger in all directions. In other words, Volkov and Yartsev may have taken the UB design as the basis and produced a larger version of it for the big 23mm cartridge.

It isn't cheap to send parcels to Canada either!

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk
Discussion forum at: http://forums.delphiforums.com/autogun/messages/

[CAPILATUS]

http://www.redrodgers.com/forums/attachment.php?attachmentid=1438

[tenmmike]

well this is easy enough to overcome if CAPILATUS provides you with info that is good enough to include into your books /data base, can't ya just send him a signed letter saying thanks? anyway iv just order assault rifles to complete my collection as a former US infantryman and sniper this will be of interest to me........if you guys do not take advantage of mr williames being here your making a very larg mistake his books are of very high quality and the info is very good

[simon]

I think it's fair to say we all appreciate having Tony on board, I've followed his comments on another discussion forum, visited his website and read a number of his online articles and I can honestly say his articles are remarkably well read and interesting, and he himself comes across as being extremely well informed and intelligent.

I do intend to post a few more or less direct questions to him myself, but I'm holding fire (pardon the pun) for the moment as a) I don't really have as much time on my hands as I would like to write, read and respond to posts and b) I don't want to bombard him with questions and scare him off.

[Tony Williams]

Aw, shucks guys - you're making me all embarrassed! [:I]

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk
Discussion forum at: http://forums.delphiforums.com/autogun/messages/

[CAPILATUS]

quote:Originally posted by Tony Williams

Hi,
Strictly speaking the ammunition for the 12.7mm ShVAK was not the same as that for the UB - it had a rimmed case, and the 20x99R was in fact made by increasing to neck size to take a 20mm shell. However, it was about the same size.
So. At last I found electronic version of Soviet’s famous book “History of aviation armament development” author A.B.Shirokorad.

It’s my free translation onto English (including name of this book), so please, don’t judge too much I hope you will understand the meaning.

…12,7mm ShVAK used the same ammo as 12,7mm army machine-guns DK and DShK.
Weight of 12,7 cartridge is 123-137gm, charge weight 17gm, cartridge length 147mm, bullet length 64,6mm, case length 108mm.
Chamber volume 20,4sm3, maximum gas pressure 3200kg/sm2 (limit for artillery system up to 1945).
B-32 bullet’s penetration 20mm of armour@90 from 350m, BZT bullet – 20mm@90 from 300m.

About B-20
… Ammo and ballistic characteristics same with 12,7mm machine-gun ShVAK.


From another source:
…therefore, it could be found a name of cartridge “12,7mm DShK”, though later on lot of weapon prototypes for all combat arms were designed for this cartridge. Overseas it’s known as 12,7x108.

…At the same time cartridge for machine-gun ShVAK was being produced with case having out flange. It had same charge and bullets as 12,7 army machine-gun. Changes in case design was explained by peculiarity of ShVAK’s auto mechanism.

So, the ammunition for the 12.7mm ShVAK was not the same as ... not exactly the same as for army machine-guns.

To provide you gents, with absolute information I've got to have two cartridges in my hand just taken out of UB and ShVAKs machine-guns feed systems!

[CAPILATUS]

Tony,
by the way in this site http://www.geocities.com/russianammo/145mm.html#3
there some confusing things.

"The cartridge has a similar appearance to the 12,7mm Degtjarjov, but with a rimmed cartridge case.
This cailber was created by necking down the 20x99R case of the 20mm ShVAK to 12,7mm. The idea was to create a new weapon by only changing the barrel"

It seems obvious that it came opposite, as ShVAK cannon appeared later on then machine-gun. Verily should be "by necking up the 12,7 case".

Your thoughts, comrade?

[Tony Williams]

I agree, the 12.7mm ShVAK case came before the 20mm.

The rimmed and rimless 12.7mm rounds, as used in the ShVAK and DShK etc repsectively, were very similar in size and performance but they were not interchangeable in the guns - which is the key point!

Incidentally, while the rimless 12.7mm DShK round is very common (it is still in service in the NSV and other MGs and heavy rifles), the rimmed ShVAK 12.7mm round is extremely uncommon - I have never seen one.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk
Discussion forum at: http://forums.delphiforums.com/autogun/messages/

[CAPILATUS]

I got a data, UB could use both 12,7x108 and 12,7x108R.
Trying to find reliable source for this information.

[Tony Williams]

That sounds extremely unlikely. The key problem would be the extractor claw, which hooks around the rim of the cartridge as it is chambered and pulls the fired case clear. These have to be sized to fit the rim. Now if you have two cartridges which are the same size and shape except that one is rimmed and the other rimless (it has a rim of course, it is just the same diameter as the case body and separated from it by an extractor groove), then the rimmmed cartridge has, by definition, a rim of significantly greater diameter and therefore would need a different extractor to fit.

I have never heard of any weapon, of any type, able to fire rimmed and rimless versions of the same cartridge except for certain revolvers chambered for the .45 Auto Rim (the same as the .45 ACP but rimmed) which could fire the ACP - but only with special clips fitted to the cases to hold them in place.

Tony Williams
Military gun and ammunition website: http://www.quarry.nildram.co.uk
Discussion forum at: http://forums.delphiforums.com/autogun/messages/