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Girandoni air rifle

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Re: Girandoni air rifle
Post by saber964   » Tue Jan 26, 2016 6:01 pm

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phillies wrote:How would the rockets be different from explosive shells?

They wouldn't hit anything.

Are 50 calibre gatlings of some merit in warfare?

During WW2 Pacific there was a Marine Air unit, or so I am told, that took some number of aircraft used in ground attach roles and tested how many machine guns they could mount on one, with the aircraft still able to perform its mission. The answer was "lots". They were used to attack Japanese surface ships, freighters and on at least one occasion a destroyed, with or so I was told dramatic results. The incoming small rounds wiped out deck crew, folks manning the unarmored AA guns, bridge crew and bridge, and set lots of fires.

Against wooden ships and ships using sails, there is considerable merit.



You're talking about the Far East Strafer. It was originally a field modified B-25C with upwards of 12 50 cal machine guns firing forward it was later put into production as the B-25H(?). Some of the aircraft were also equipped with a 75mm howitzer. They also modified PBY Catalina's known as Black Cats with 6 50 cal the gunner actually sat on a saddle of asbestos over gun barrels to fire the guns. An example of how these planes fought read up on the battle of the Bismarck Sea.
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Re: Girandoni air rifle
Post by lyonheart   » Tue Jan 26, 2016 8:14 pm

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Hi Saber964,

It was a 75mm cannon that was mounted in the B-25G and H, not the 75mm howitzer which fired a much lighter, rather lower velocity shell that would have been quite inadequate.

While I'm familiar with the 'Black Cats', using 6 .50's as a gunship in something so slow seems counter indicated.

L


saber964 wrote:
phillies wrote:How would the rockets be different from explosive shells?

They wouldn't hit anything.

Are 50 calibre gatlings of some merit in warfare?

During WW2 Pacific there was a Marine Air unit, or so I am told, that took some number of aircraft used in ground attach roles and tested how many machine guns they could mount on one, with the aircraft still able to perform its mission. The answer was "lots". They were used to attack Japanese surface ships, freighters and on at least one occasion a destroyed, with or so I was told dramatic results. The incoming small rounds wiped out deck crew, folks manning the unarmored AA guns, bridge crew and bridge, and set lots of fires.

Against wooden ships and ships using sails, there is considerable merit.



You're talking about the Far East Strafer. It was originally a field modified B-25C with upwards of 12 50 cal machine guns firing forward it was later put into production as the B-25H(?). Some of the aircraft were also equipped with a 75mm howitzer. They also modified PBY Catalina's known as Black Cats with 6 50 cal the gunner actually sat on a saddle of asbestos over gun barrels to fire the guns. An example of how these planes fought read up on the battle of the Bismarck Sea.
Any snippet or post from RFC is good if not great!
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Re: Girandoni air rifle
Post by DDHvi   » Tue Jan 26, 2016 11:23 pm

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lyonheart wrote:Hi Weird Harold,

snip

Since HEAT warheads depend on the Monroe effect, which hasn't been discovered yet on Safehold according to the textev, they're not an option against the screw galleys.

snip



Is the Monroe effect that item where an explosive charge with an internal forward facing cone lined with metal produces an extremely high velocity squirt of metal on explosion? If not, please give a short exposition.
:?:
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Dumb mistakes are very irritating.
Smart mistakes go on forever
Unless you test your assumptions!
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Re: Girandoni air rifle
Post by AirTech   » Fri Jan 29, 2016 9:00 am

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lyonheart wrote:Hi Saber964,

It was a 75mm cannon that was mounted in the B-25G and H, not the 75mm howitzer which fired a much lighter, rather lower velocity shell that would have been quite inadequate.

While I'm familiar with the 'Black Cats', using 6 .50's as a gunship in something so slow seems counter indicated.

L


[


The 75mm round had the advantage of being fired from a platform moving at 3OO kts - adding 500 feet per second to the muzzle velocity (or 25% on the standard land based gun). The original gun was the 75mm M3 tank gun but was down sized due to blast damage to the aircraft.

The Black Cats advantage was their range - they popped up thousands of miles behind the Japanese front lines to attack shipping. (And were originally based on lakes in southern Australia, flown 4000 miles to forward bases, and refueled for a strike and then reversed the process on the way back). 36 hour unrefueled missions were common. The Qantas Cats flew 32 hour passenger operations on a weekly basis (Perth to Kogala).
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Re: Girandoni air rifle
Post by lyonheart   » Fri Jan 29, 2016 2:44 pm

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Hi DDHvi,

Yup, you got it. ;)

L


DDHvi wrote:
lyonheart wrote:Hi Weird Harold,

snip

Since HEAT warheads depend on the Monroe effect, which hasn't been discovered yet on Safehold according to the textev, they're not an option against the screw galleys.

snip



Is the Monroe effect that item where an explosive charge with an internal forward facing cone lined with metal produces an extremely high velocity squirt of metal on explosion? If not, please give a short exposition.
:?:
Any snippet or post from RFC is good if not great!
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Re: Girandoni air rifle
Post by lyonheart   » Fri Jan 29, 2016 2:51 pm

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Hi Air Tech,

Loaded down with guns, I don't believe any B-25G or H ever did 300 knots on a firing pass, or even 345 mph at altitude, since that had become less important than payload and firepower.

I know the PBY's had better payload range with 4000 lbs [such as 4 X 1000 lb bombs or torpedo's] than the vaunted B-17's, but I believe the strikes you cite were using just a pair of torpedoes, not 4 of them.

L


AirTech wrote:
lyonheart wrote:Hi Saber964,

It was a 75mm cannon that was mounted in the B-25G and H, not the 75mm howitzer which fired a much lighter, rather lower velocity shell that would have been quite inadequate.

While I'm familiar with the 'Black Cats', using 6 .50's as a gunship in something so slow seems counter indicated.

L


[


The 75mm round had the advantage of being fired from a platform moving at 3OO kts - adding 500 feet per second to the muzzle velocity (or 25% on the standard land based gun). The original gun was the 75mm M3 tank gun but was down sized due to blast damage to the aircraft.

The Black Cats advantage was their range - they popped up thousands of miles behind the Japanese front lines to attack shipping. (And were originally based on lakes in southern Australia, flown 4000 miles to forward bases, and refueled for a strike and then reversed the process on the way back). 36 hour unrefueled missions were common. The Qantas Cats flew 32 hour passenger operations on a weekly basis (Perth to Kogala).
Any snippet or post from RFC is good if not great!
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Re: Girandoni air rifle
Post by saber964   » Fri Jan 29, 2016 5:23 pm

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The black cats were night hunters. They would fly out of Guadalcanal and Port Morsby at dusk and go hunting for anything they could find barges, landing craft, merchants, warships on occasion.
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Re: Girandoni air rifle
Post by peke   » Wed Feb 03, 2016 1:34 pm

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I read somewhere (can't remember where exactly) that the shaped-charge effect was discovered by accident, like this: someone was doing some testing with explosive charges and armor plate, and the explosive charge in question had been accidentally pressed against a series of numbers in relief, so the metal-facing charge surface had letter-sized indentations. When the charge blew and the smoke cleared, the someone in question was surprised to discover that the plate was largely intact, but that the numbers had become gouged in the plate.

Is there any truth to this? Because I can totally see someone in Howswym's explosive shop accidentally doing something like this (or maybe set up to accidentally "discover" it)
------------------------------------------------------
There is no problem so complex that it cannot be solved through the judicious application of high-power explosives.
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Re: Girandoni air rifle
Post by Expert snuggler   » Wed Feb 03, 2016 2:43 pm

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A fixed position, like a fortress, could have a steam-powered air compressor and distribution lines. Wouldn't there be an advantage to needing to store less powder and not being limited by the cartridge manufacturing bottleneck?

Could you go full auto if not limited by fouling from black powder?
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Re: Girandoni air rifle
Post by phillies   » Wed Feb 03, 2016 2:54 pm

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peke wrote:I read somewhere (can't remember where exactly) that the shaped-charge effect was discovered by accident, like this: someone was doing some testing with explosive charges and armor plate, and the explosive charge in question had been accidentally pressed against a series of numbers in relief, so the metal-facing charge surface had letter-sized indentations. When the charge blew and the smoke cleared, the someone in question was surprised to discover that the plate was largely intact, but that the numbers had become gouged in the plate.

Is there any truth to this? Because I can totally see someone in Howswym's explosive shop accidentally doing something like this (or maybe set up to accidentally "discover" it)


I have read the same, the indents being pressed in the explosive during casting.
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