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Machine Guns and Cannons (Ground, Vehicle, and Aircraft Mounted Weapons)

Started by Archibald, June 30, 2007, 12:51:24 AM

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Cliffy B

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dy031101

Quote from: Cliffy B on March 20, 2012, 08:15:01 AM
http://www.navweaps.com/Weapons/WNUS_16-50_mk2.htm

All you probably ever wanted to know  ;D

So is it likely that the preliminary design would have looked like the one used by BB-49 class, just with a smaller barbette?
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dy031101

Does anyone know if the 105mm L/44 gun on the Super Sherman would be capable of impart energy at least comparable to the 90mm F4 gun on the French ERC 90 F4 Sagaie?

I know the 105mm L/44 gun was originally intended to mainly use HEAT rounds against tanks, but given the potential for even the likes of T-54/55 to be given modern applique armours, I wonder if the gun can remain somewhat serviceable with, say, sub-caliber penetrators from smaller anti-tank guns.
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rickshaw

You'd unlikely see any major advantage in doing so.  The Israeli modified French CN-105-57 gun (locally designated the CN-105 D1) was extensively modified being cut down to 44 calibres and having a much reduced charge to decrease the recoil to make it fit inside a Sherman turret.   I've been unable to find the muzzle velocity of either the CN-105-57 or the CN-105 D1 nor has one for the 90mm on the ECR-90.  I suspect the CN-105 D1's MV wasn't much higher though.
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Weaver

Here's data for the ERC's long-barrelled 90mm gun:

Property : Value
Main weapon caliber (mm) : 90
Length (mm) : 5740
Barrel length (calibres) : 52
Recoil stroke (mm) : 550
Weight (kg) : 602
Recoiling mass (kg) : 420
Muzzle velocity (m/s) : 1275
Firing range (m) : 1660

From here: http://www.army-guide.com/eng/product3586.html

An old book I've got lists the penetration of the gun as 320mm, but it doesn't qualify that for range or angle, unfortunately.


Here's data from the same source on the CN105G1 gun which is the latest version of the CN-105-57:

Property : Value
Main weapon caliber (mm) : 105
Length (mm) : 4622
Recoil stroke (mm) : 368
Weight (kg) : 1210
Muzzle velocity (m/s) : 1460


Can't find really good info on the CN-105 D1, but I keep seeing a muzzle velocity figure of 800 m/s mentioned.

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dy031101

I see......

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I've been hearing people putting the US medium tank grade 90mm guns into the same category as the German 88mm L/56 whereas the Russian 100mm gun is seen as being on the same level as the more-powerful 88mm L/71.  Did the 90mm gun actually have unrealized potential, and if so, would ammunition technology of the 1980s have been able to keep the gun reasonably useful (the French 90mm F4 gun being the one measuring stick I can find) as an anti-tank weapon?
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DarrenP

Great Britain and most of the commonwealth used the a .303 version of the Browning M1919 in their aircraft and on Lease Lend vehicles like the Sherman the .30'06 version and in UK made vehicles the BESA in 7.92mm a cezch design (Like the Bren). It always struck me as strange that they didn't standardise onto a .303 Browning and introduce a ground mounted one to come between the Bren and the Vickers!

rickshaw

Quote from: DarrenP on November 23, 2014, 11:26:52 PM
Great Britain and most of the commonwealth used the a .303 version of the Browning M1919 in their aircraft and on Lease Lend vehicles like the Sherman the .30'06 version and in UK made vehicles the BESA in 7.92mm a cezch design (Like the Bren). It always struck me as strange that they didn't standardise onto a .303 Browning and introduce a ground mounted one to come between the Bren and the Vickers!

Why?  It didn't fit into the British "ethos" (they didn't have a doctrine as we understand the term) of how the army was meant to operate.   The Browning simply wasn't needed.  You must also remember, the British Army was far more interested in accuracy than sheer firepower in the period between the wars when the aberration which was WWI was not seen as typical of how it was going to be employed in the future.  The British Army was an imperial police force, used to show the flag and quell the occasional native uprising.   Firepower wasn't generally needed or wanted.  The Vickers was more than adequate, while the Bren was perfect, supplying automatic fire in short, controlled bursts.   Columns of troops on extended campaign, deep in the mountains/velde/jungle just could be profligate with its fire, and the Bren fulfilled that niche wonderfully.
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Howard of Effingham

hmm, is/are there many reasons why the mostly german idea of 'Schrage musik' or those rather
effective upward firing 20 or 30 mm cannon on nightfighters from ww2 weren't if at all much used after
the war?

they could have been useful against some of the larger bomber a/c, whatever airforce they were from.
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PR19_Kit

Perhaps because the various air forces wanted to shoot down the bombers at greater range after WWII? To get a Schrage Musik system to work properly you needed to be REALLY close in.
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Weaver

Quote from: DarrenP on November 23, 2014, 11:26:52 PM
Great Britain and most of the commonwealth used the a .303 version of the Browning M1919 in their aircraft and on Lease Lend vehicles like the Sherman the .30'06 version and in UK made vehicles the BESA in 7.92mm a cezch design (Like the Bren). It always struck me as strange that they didn't standardise onto a .303 Browning and introduce a ground mounted one to come between the Bren and the Vickers!

What Rickshaw said, plus the .303 Browning was a specifically RAF project for the purposes of arming the new 8-gun fighters, and inter-service rivalry being what it was (and is) that alone would be enough to ensure that the other two services wouldn't take it. As for the rest of the calibre mish-mash, well most of it happened after the war had started or immediately before, and getting things into production was more important than spending agesw redesigning them to different calibres. In the case of the BESA, I beleive it could have been converted, but they elected not to because it wasn't seen as cost-effective: the tank Corps had a different logistics structure from the infantry anyway, so the fact that 7.92mm BESA was specific to tanks wasn't seen as a big deal.
"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

"I dunno, I'm making this up as I go."
 - Indiana Jones

Weaver

Quote from: Howard of Effingham on December 05, 2014, 08:51:27 AM
hmm, is/are there many reasons why the mostly german idea of 'Schrage musik' or those rather
effective upward firing 20 or 30 mm cannon on nightfighters from ww2 weren't if at all much used after
the war?

they could have been useful against some of the larger bomber a/c, whatever airforce they were from.

There were certainly a few schemes drawn up with them, but none were flown. There were also a number of attempts to fit elevating and/or tracking cannons to fighters, but they didn't get past flight testing. The principle interception problems post-war were:

1.Nuclear weapons had made it imperitive to shoot bombers down as far away as possible and as soon as possible,

2. The jet engine had eaten a lot of the fighter's speed advantage over the bomber.

The results of both those was that fighters needed a quick kill from the longest range, which drove the development of guided missiles. Having to chase down a bomber that was only a little slower took quite long enough if you only had ot get into missile/cannon range behind it. Adding more time to get underneath it was unacceptable. The other option was the head-on shot, but cannon didn't have enough range for this, given the ferocious closing speeds. The head-on problem lead first to unguided rocket barrages, then to nuclear warheads, until eventually good enough fire control systems and conventional missiles were developed.
"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

"I dunno, I'm making this up as I go."
 - Indiana Jones

kitnut617

Quote from: Weaver on December 05, 2014, 11:18:03 AM
Quote from: Howard of Effingham on December 05, 2014, 08:51:27 AM
hmm, is/are there many reasons why the mostly german idea of 'Schrage musik' or those rather
effective upward firing 20 or 30 mm cannon on nightfighters from ww2 weren't if at all much used after
the war?

they could have been useful against some of the larger bomber a/c, whatever airforce they were from.

There were certainly a few schemes drawn up with them, but none were flown. There were also a number of attempts to fit elevating and/or tracking cannons to fighters, but they didn't get past flight testing. The principle interception problems post-war were:

1.Nuclear weapons had made it imperitive to shoot bombers down as far away as possible and as soon as possible,

2. The jet engine had eaten a lot of the fighter's speed advantage over the bomber.

The results of both those was that fighters needed a quick kill from the longest range, which drove the development of guided missiles. Having to chase down a bomber that was only a little slower took quite long enough if you only had ot get into missile/cannon range behind it. Adding more time to get underneath it was unacceptable. The other option was the head-on shot, but cannon didn't have enough range for this, given the ferocious closing speeds. The head-on problem lead first to unguided rocket barrages, then to nuclear warheads, until eventually good enough fire control systems and conventional missiles were developed.

Plus the fact modern bombers have a pretty good rear-looking radar and defences
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Weaver

Quote from: kitnut617 on December 05, 2014, 02:45:56 PM
Plus the fact modern bombers have a pretty good rear-looking radar and defences

Indeed: try sneaking up on a Bear and formating underneath it and you'll be looking down the wrong end of a pair of NR-23s...
"Things need not have happened to be true. Tales and dreams are the shadow-truths that will endure when mere facts are dust and ashes, and forgot."
 - Sandman: A Midsummer Night's Dream, by Neil Gaiman

"I dunno, I'm making this up as I go."
 - Indiana Jones

Old Wombat

Quote from: Weaver on December 05, 2014, 03:06:22 PM
Quote from: kitnut617 on December 05, 2014, 02:45:56 PM
Plus the fact modern bombers have a pretty good rear-looking radar and defences

Indeed: try sneaking up on a Bear and formating underneath it and you'll be looking down the wrong end of a pair of NR-23s...

Or a Vulcan, back in the days when B-52's carried them.
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