dandy_don
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Cannon Or Machine Gun?

Sat Jan 06, 2007 12:51 pm

I am watching the History Channels show on the air battles over Guadelcanal. The F4 used 50 cal machine guns the Zero a 20mm cannon. What is the difference?

What would you want your plane to have?
 
Acheron
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RE: Cannon Or Machine Gun?

Sat Jan 06, 2007 3:13 pm

Quoting Dandy_don (Thread starter):
What is the difference?

Less ammo for the 20mm.

Quoting Dandy_don (Thread starter):

What would you want your plane to have?

Both.
 
Ozair
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RE: Cannon Or Machine Gun?

Sat Jan 06, 2007 4:10 pm

Quoting Dandy_don (Thread starter):
What is the difference?

The size (diameter) of the shell

Quoting Dandy_don (Thread starter):
What would you want your plane to have?

A selective mix would be nice but it really depends upon your mission. For air to air battles in WW2 the cannon equipped aircraft usually only had to score one or two hits to bring down an opponent. Compare that to the Spitfires and Hurricanes of the Battle of Britain which fired the ineffective .303 and had a terrible time trying to bring down German bombers.

Still the Mustang which destroyed more aircraft in Europe than any other was armed with 4 and then 6 .50. I guess the P-51 flew mainly against Axis fighter aircraft compared to Axis fighters combating a full range of allied aircraft.
 
bilgerat
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RE: Cannon Or Machine Gun?

Sat Jan 06, 2007 7:56 pm

A machine gun is a lighter and smaller weapon which fires solid slugs of metal - in the case of machine guns that I am familiar with they are simply lead cased in copper. A cannon, on the other hand, fires larger and heavier explosive or incendiary shells which explode upon contact. Generally speaking, a cannon will be larger than a machine gun, carry less ammunition, but that ammunition causes far more damage to the target.A cannon also has greater effective range.

Early war fighters carried rifle calibre machine guns, and a few of them had a cannon too. As the war progressed and aircraft were fitted with armour plating the rifle calibre weapons gave way to heavy machine guns and more cannons.
 
Kukkudrill
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RE: Cannon Or Machine Gun?

Sun Jan 07, 2007 12:54 am

I read somewhere that the Spitfire's cannon fired alternating solid and explosive shells though I don't recall the source.

I have, however, found data on the weight of fire of various Spitfire marks which graphically illustrates the difference between cannon and machine-guns. The figures below refer to the weight of the projectiles fired during a 3-second burst.

Mark I (8 x .303 inch machine-guns): 8lb
Mk Vb (2 x 20mm cannon, 4 x .303" machine-guns): 20lb
Mk XVIII (2 x 20mm cannon, 2 x .5" machine-guns): 26lb
Mk 24 (4 x 20mm cannon): 40lb.
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Devilfish
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RE: Cannon Or Machine Gun?

Sun Jan 07, 2007 1:11 am

Well, Defense Industry Daily reports that the US Naval Air Systems Command has just issued a $9.4M change to an existing contract for the procurement of 34 20mm M61A2 Vulcan cannons for the Super Hornet.....

http://www.defenseindustrydaily.com/...cannons-on-super-hornets/index.php

Quote:
"The 20mm M61 Vulcan is a hydraulically driven, six-barreled, air-cooled, electrically fired Gatling gun with an extremely high rate of fire. It has been the principal cannon armament of United States military aircraft for five decades. The M61A2 is mechanically the same as the M61A1, but with thinner barrels to reduce overall mass to 202 lb (91.6 kg)."
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dl021
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RE: Cannon Or Machine Gun?

Sun Jan 07, 2007 2:03 am

During the Second World War the difference was pronounced by rate of fire, reliability and ammo portability (number of rounds that could be carried).
Targeting ability was also a problem. The accurately delivered throw weight of a 6 or 8 .50cal armament package compared to a 20mm package was significantly higher.

Quoting Acheron (Reply 1):
Less ammo for the 20mm.

slower rate of fire.

The modern use of high speed cannon makes it more favorable when it's combined with the greater ability of the jets to carry the extra ammo needed to make it useful.
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kc135topboom
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RE: Cannon Or Machine Gun?

Sun Jan 07, 2007 2:26 am

Quoting BilgeRat (Reply 3):
A machine gun is a lighter and smaller weapon which fires solid slugs of metal - in the case of machine guns that I am familiar with they are simply lead cased in copper. A cannon, on the other hand, fires larger and heavier explosive or incendiary shells which explode upon contact.

That was not always the case with the US M-2 (called Ma Duce) .50 caliber heavy machine gun. The ammo belts carried a mix of different ammo types. Usually 2 AP rounds followed by 3 anti personnel rounds, followed by one tracer round. Incenderary and small explosive rounds could also be fired, but aircraft usually did not carry explosive rounds.

The diameter of the .50 caliber round is 1/2", or 12.5mm. That is not much smaller than the 20mm rounds fired by the IJN/IJAF A6M Zero fighters. But, the M-2 does have a much higher ROF.

BTW, the M-2 HMG, in all it's different forms has been in continous use by the US Military since 1917. It is also used by many other countries militaries since WWII (Allied Forces) and even Japan, Germany, and Italy since shortly after WWII.
 
L-188
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RE: Cannon Or Machine Gun?

Sun Jan 07, 2007 5:19 am

The cannon was still relatively new when WWII started. At that time there where questions of reliablity, the weight of the weapon and rate of fire.

Rate of fire comes in when you are trying to put as much fire on a target that may only be in your site for only a couple of seconds at most.

That is one of the reasons why there was such a debate on cannons vs .303's during the BOB. Some pilots felt you where going to do more damage with 8 .303 tearing holes in the target then you would getting only 1 or 2 cannon hits during the same time frame.

I personally think the US had a pretty good thing going with their clusters of 4,6,8 .50 cal guns. But I do note that they did have fighters that where mounting cannon at the start of the war (P-39, P-38) and several types that where mounting them at the end, (F4U)
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deskflier
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RE: Cannon Or Machine Gun?

Sun Jan 07, 2007 3:45 pm

The difference between HMG and cannon is illustrated by this comparison between the F-86 Sabre and the MiG-15.

The F-86 was armed with six .50s. (Some export customers, like Canada, ordered the Sabre with four Hispano 20mm cannon from the outset.) These weapons had pinpoint accuracy and US pilots scored multiple hits on their targets. However, the sturdy MiG could take the entire ammo load of a F-86 without becoming unflyable. (The Chinese and North Korean pilots often bailed out of fully functional planes just because they were taking hits. Poor training.)

The MiG-15 was armed with two 23mm and one 37mm cannon. These weapons were chosen to quickly dispose of nuclear-armed B-29s. For fighter-vs-fighter combat these cannon (especially the 37mm) didn´t have the necessary accuracy, however. A MiG pilot could spend his entire ammo load without scoring a single hit. When they got the occasional lucky hit, the F-86 usually disintegrated. Both the 23mm and the 37mm started their life as antitank weapons on the Il-2 Shturmovik. (The 37mm actually as an infantry close-defence weapon)

The lessons learned from Korea, prompted the switch from the .50 M3 to the 20mm six-barrel M61 in the USAF and the development of a new accurate 30mm cannon in the Soviet Union.
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L-188
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RE: Cannon Or Machine Gun?

Mon Jan 08, 2007 2:07 pm

Quoting Deskflier (Reply 9):
(The 37mm actually as an infantry close-defence weapon)

Here is a question, does the 37mm in the Mig-15 have any relation to the 37mm that was installed in the P-39, large numbers of which where supplied to the Soviets under Lend-Lease.

I know in the US, that cannon was also used in some light tanks, and was also popular as a bow mounted gun on PT boats.
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ex52tech
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RE: Cannon Or Machine Gun?

Mon Jan 08, 2007 2:29 pm

Ok guys, one of the biggest problems with the cannons used during WWll was muzzle velocity.

The M-2 .50cal had a high muzzle velocity and is a very flat shooting gun, the lower muzzle velocity cannon rounds dropped off quickly. Cannon equiped aircraft had to use more deflection when shooting at another aircraft, and generally had to be closer to their target.

The ME-262 with the MK 108 30mm cannons were almost useless in strafing ground targets due to the cannon's low muzzle velocity, you could fly the aircraft into the ground before you could see ground strikes of the cannon shells.
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deskflier
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RE: Cannon Or Machine Gun?

Tue Jan 09, 2007 1:15 am

Quoting L-188 (Reply 10):
Here is a question, does the 37mm in the Mig-15 have any relation to the 37mm that was installed in the P-39, large numbers of which where supplied to the Soviets under Lend-Lease.

I have no sources at hand on this, but my recollection of things is that the MiG-15 37mm was an all-Russian weapon, used as a towed AT-gun, in light tanks(eg, the T-26), and in ground attack aircraft, such as Il-2m3 and Yak-9T. It may not even have fired the same ammunition as the American 37mm gun. Or it could be derived from the Soviet (unauthorised) copy of the Bofors 40mm.
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deskflier
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RE: Cannon Or Machine Gun?

Tue Jan 09, 2007 1:27 am

Quoting Ex52tech (Reply 11):
Ok guys, one of the biggest problems with the cannons used during WWll was muzzle velocity.



Quoting Ex52tech (Reply 11):
The ME-262 with the MK 108 30mm cannons were almost useless in strafing ground targets due to the cannon's low muzzle velocity, you could fly the aircraft into the ground before you could see ground strikes of the cannon shells.

The Germans used another 30mm, the MK103, weighing almost the double compared to the MK108. The MK103 had reasonable ballistics, like the MG151/20. The MK103 was first used as a podded AT-gun under the belly of the Henschel Hs129 "Flying can-opener". It worked well thanks to its high-velocity projectiles.
The 20mm MG151/20 was a development of the 15mm MG151. The shells of the 15mm weapon was not powerful enough and the older 20mm MG FF was one of the low-velocity weapons. (The Wehrmacht didn´t want the MG FF because of its poor armour-piercing characteristics.) The MG151/20 was to (and did) combine the strong points of both weapons.
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SlamClick
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RE: Cannon Or Machine Gun?

Tue Jan 09, 2007 3:30 am

Quoting BilgeRat (Reply 3):
A machine gun is a lighter and smaller weapon which fires solid slugs of metal - in the case of machine guns that I am familiar with they are simply lead cased in copper.

The .50 caliber one that went through the shutter next to my head in 1968 was armor-piercing and had a steel core, surrounded by a layer of lead with a copper jacket. It must have been a ricochet because it did not penetrate the brick wall.

Quoting KC135TopBoom (Reply 7):
The diameter of the .50 caliber round is 1/2", or 12.5mm. That is not much smaller than the 20mm rounds

I'd like to see the numbers on them but the fifty is probably less than half the "horsepower" of the 20mm that our forces use. Amount of powder, bullet weight and muzzle energy have got to be twice that of the fifty.

Quoting KC135TopBoom (Reply 7):
the US M-2 (called Ma Duce) .50 caliber heavy machine gun

Moral objections to their intended purpose aside, this has to be one of the ten best machines ever designed. These things will soldier on reliably into my grandchildrens' time. Sadly, that will probably be quite necessary.

Near my "home" in Vietnam there were, side by side, an American headquarters unit and an ARVN compound. From time to time they would be probed by the Vietcong during the night. Apparently they did not keep the Ma Deuces mounted all the time. I'd hear sporadic rifle fire first, AKs answered by M14s mostly. Then the five foot tall ARVNs who manned the BARS would open up. Very distinctive sound, easy to tell from the M14.

After a few minutes, and maybe a grenade or two, maybe an M79, the M2 would open up. From that point to the end of the VC probe was measured in seconds. There was no hiding from those bad boys. It would shoot through every house between the compound and the river.

I always felt sorry for the civilians who lived on that particular infiltration route. Caught in the middle like that.
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kc135topboom
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RE: Cannon Or Machine Gun?

Tue Jan 09, 2007 3:45 am

Quoting SlamClick (Reply 14):
After a few minutes, and maybe a grenade or two, maybe an M79, the M2 would open up. From that point to the end of the VC probe was measured in seconds. There was no hiding from those bad boys. It would shoot through every house between the compound and the river.

It seems almost everyone has a lot of respect for Ma Duce, no matter which end of the weapon you happened to be standing.

Quoting SlamClick (Reply 14):
Quoting KC135TopBoom (Reply 7):
the US M-2 (called Ma Duce) .50 caliber heavy machine gun

Moral objections to their intended purpose aside, this has to be one of the ten best machines ever designed. These things will soldier on reliably into my grandchildrens' time. Sadly, that will probably be quite necessary.

I agree with you, the M-2 is one of the 10 best designed machines of all time. Reluctantly, I also agree that my Grandsons, and future Great Grandsons will still have to be using the old "Ma Duce".

Browning did a great job on this gun.
 
SlamClick
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RE: Cannon Or Machine Gun?

Tue Jan 09, 2007 6:05 am

Quoting Dandy_don (Thread starter):
What would you want your plane to have?

Four 20mm in the nose and four .50 cal in the wings.
Two R-2800 engines with testosterone injection.

In short, one of these:

View Large View Medium
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Photo © Vladimir Kostritsa
View Large View Medium
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Photo © John Allan


Man I literally ache to fly one of these! You can keep your P-38. And if there is an ounce of fighter pilot in your soul you have to imagine what this would have done to a Zero. Can you say "aluminum confetti?"
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bilgerat
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RE: Cannon Or Machine Gun?

Tue Jan 09, 2007 6:46 am

Relating to the subject of guns and such like....

Last month I attended the RFA Weapons Maintenance Officer's Course at HMS Collingwood. One of the instructors was discussing the difference between the 7.62mm and the 5.56mm round. He said the 5.56mm round used by NATO was adopted because it is not as lethal as the 7.62mm. Apparently a hit from a 7.62mm round will more likely than not kill you outright, but a hit from a 5.56mm round will leave you seriously wounded and making a lot of noise, prompting one or more of your comrades to come along and drag you off the battlefield, effectively removing not only you, but a couple of your mates as well from the battle. Anyone know if there is any truth to this?

We also discussed the SLR (the weapon used by the British soldier prior to the L85/SA80). This was a 7.62mm weapon, and apparently very powerful. We were told a story about a young girl shot through the head with a 7.62mm round whilst playing at school. It was found a soldier had a negligent discharge on a range several miles away, and this was where the fatal bullet came from.

We got to see a video from the first Gulf War of a live fire practice from an RN minesweeper in the Gulf. It showed a guy firing a 30mm cannon where the barrel hadn't been reattached properly. The gunner operating the weapon disappeared in a huge cloud of smoke and the 12ft barell went sailing over the side of the ship. The gunner emerged from the smoke looking rather dazed and his anti-flash was more than a little singed. Apparently this is known as "Doing a William Tell"  Smile We also got to see some 20mm and 30mm barells that had been fired when the bore was not totally dry - pretty impressive to see these large barrels literall burst open from the forces produced by the gas propellant.

The moral of the story: Before firing make sure the barell is properly attached and is totally dry. Check, check and double check!
 
SlamClick
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RE: Cannon Or Machine Gun?

Tue Jan 09, 2007 6:50 am

Quoting BilgeRat (Reply 17):
The moral of the story: Before firing make sure the barell is properly attached and is totally dry.

In another life I qualified (to be a Huey doorgunner) on the M-60 machinegun. Standard issue came with two barrels. The infantry could alternate for heat dissipation. IIRC the thing was just held in place with a camlok and I later wondered about it flying downrange as you describe. In peacetime an amusing anecdote. In combat a catastrophe!
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MD11Engineer
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RE: Cannon Or Machine Gun?

Wed Jan 10, 2007 1:17 am

Quoting SlamClick (Reply 18):
Quoting BilgeRat (Reply 17):
The moral of the story: Before firing make sure the barell is properly attached and is totally dry.

In another life I qualified (to be a Huey doorgunner) on the M-60 machinegun. Standard issue came with two barrels. The infantry could alternate for heat dissipation. IIRC the thing was just held in place with a camlok and I later wondered about it flying downrange as you describe. In peacetime an amusing anecdote. In combat a catastrophe!

This happened with the Czech VZ-26 (the precedessor of the venerable Bren light machine gun used by the British and Commonwealth forces during WW2 and beyond) during a demonstration to potential customers.
Afterwards the barrel locking latch was modified, so that the bolt would not drive into battery with the latch not fully locked. I experienced a few stoppages with a Bren due to this, which I couldn't explain (mind, I learned the use of this gun from manuals, books and veteran accounts, not through an instructor) until I found out about it.

Jan

[Edited 2007-01-09 17:18:22]
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deskflier
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RE: Cannon Or Machine Gun?

Wed Jan 10, 2007 3:57 am

Quoting BilgeRat (Reply 17):
difference between the 7.62mm and the 5.56mm round.

The switch from calibres in the 8mm class to 5.56mm and the like came about as a result of WW2 experience. The major powers went into WW2 with two types of personal firearms. 1) The bolt-action repeating or semi-automatic rifle, loaded with a high-powered cartridge of 7 to 8mm calibre and with an effective range of 800 to 1000m (0.5 to 0.6miles). Its main drawback being the 5km(3mile) safety distance when practising. 2) The sub-machinegun loaded with pistol ammo of 7.5 to 9mm calibre and with an effective range of less than 200m (650ft). This one was fully automatic with a rate of fire of some 600rpm.
The strong points of these two weapons were combined into the modern assault rifle. It had a choice between semi-automatic and fully cyclic fire, and was to be most effective at ranges between 25 and 300m (80 and 1000ft respctively). Since the power of the old rifle-ammo wasn´t needed a smaller ammunition was chosen, to lessen recoil and to shorten safety distances. Less recoil meant that the rifle could be lighter and when both rifle and ammo were lighter, more rounds could be carried.
On the issue of wounding rather than killing enemies, I know of two weapons purposely built for this. First, in WW2 the Japanese used a 4mm(.157in) rifle. And second, in Vietnam Special Forces - I don´t know whether US or Red - used plastic bullets that didn´t show on X-ray.
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kc135topboom
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RE: Cannon Or Machine Gun?

Wed Jan 10, 2007 4:19 am

Quoting BilgeRat (Reply 17):
One of the instructors was discussing the difference between the 7.62mm and the 5.56mm round. He said the 5.56mm round used by NATO was adopted because it is not as lethal as the 7.62mm. Apparently a hit from a 7.62mm round will more likely than not kill you outright, but a hit from a 5.56mm round will leave you seriously wounded and making a lot of noise, prompting one or more of your comrades to come along and drag you off the battlefield, effectively removing not only you, but a couple of your mates as well from the battle. Anyone know if there is any truth to this?

That is not true. The 5.56mm (.223 caliber) was selected so more rounds could be carried by each person. In the US, this is the M-16, M-4, etc. The 5.56mm round is also intended for closer range battles (300m or less) and is a general application weapon. The 7.62mm (30 caliber) round is intended for special application guns, such as the M-60 MMG. It is also ment for battles out to 500m. Both the 5.56mm and 7.62mm rounds are entended to kill the enemy, wounding him can be done with either round. Also the 5.56mm does have a higher muzzle velocity than the 7.62mm. The 9mm hand guns are a last resort self defense weapon.
 
SlamClick
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RE: Cannon Or Machine Gun?

Wed Jan 10, 2007 4:54 am

My memory of the M16 training I had was that the smaller caliber, higher velocity round (compared with the 7.62 of the M14) was justified by "hydrostatic shock" Because a flesh wound was alleged to shatter nearby bones it was supposed to be more effective against human targets than the 30-06 or 7.62 NATO it replaced.

The criticism took two major forms.

1. The very high velocity projectile was said to go unstable or even disintegrate when hitting foliage, making it a poor choice for a jungle war.

2. The mechanism was said to be too close-spaced and confined to tolerate the introduction of any dirt, mud, etc to the action. Read David Hackworth's account of digging an AK-47 our from under a dead-and-buried Vietcong. He fired off the entire clip on full auto without first cleaning the weapon to illustrate to his troops the weapon they were up against.

I came to believe that an important function of the rifle was to give confidence to the man carrying it. If you are advancing through the brush or the jungle and you can spit fire and very loud noises downrange at high rates of fire then your courage to advance is greatly increased - despite the fact that not one round in many thousands actually destroys a target. When faced with enemy forces numbering in the 100-200 range, if we had a body count of twenty afterwards that would be quite a victory. This on the expenditure of ten of thousands of rounds and possibly support from artillery, gunships or Air Force airstrikes.

I believe it was a very wise move on the part of the Army to make the burst of three rounds the normal "auto" mode.
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L-188
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RE: Cannon Or Machine Gun?

Wed Jan 10, 2007 12:09 pm

[

Quoting Deskflier (Reply 20):
First, in WW2 the Japanese used a 4mm(.157in) rifle.

4mm? Never heard of it, and wounding your enemy does seem in my mind to go against the prevailing Bushito warrior code at the time.

I am familiar with the 6.5 Jap cartridge, which they realized was underpowered during their operation in Manchuria, which is why they went to the 7.7 Jap.

I am curious to hear more.

I

Quoting Deskflier (Reply 20):
Since the power of the old rifle-ammo wasn´t needed a smaller ammunition was chosen, to lessen recoil and to shorten safety distances. Less recoil meant that the rifle could be lighter and when both rifle and ammo were lighter, more rounds could be carried.

Welll part of the issue was that there where only 1 rifle that was successful rifle that was able to handle a full sized round, and that was the M1 Grand and her 30.06 round. We also had the Johnson rifles but those where not issued on a wide scale. The Russians did develop the SVT and AVT Tokerev rifles using the slightly smaller 7.62 rimmed russian round. But they had a lot of problems during development of the round. The Germans had a couple of rifles and from what I understand they where satisfactory, but not enough to put on large issue, and in the end developed the shortened Kurtz round when they developed the first, "Assault Rifle" (Damm I hate that term, but that is what Hitler named it) That round inspired the soviets to develop their modern 7.62 round for the SKS and AK-47.

That is why the US when ahead and shortened the 30.06 to make the .308 or the 7.62 and the Russians and Germans made their shortened rounds. It was just simplere to deal with the lesser power of these rounds.
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NKP S2
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RE: Cannon Or Machine Gun?

Sun Jan 14, 2007 11:43 am

In regards to the original topic question; Every machine gun is not the same, nor is every cannon. No need to discuss the "fifty" as it has been detailed so well already.

In the case of the Mitsubishi Zero, several different cannon were used. The earlier model Zeros ( A6M2, A6M3 ) used cannon ( very similar to the cannon used on Bf109 E models ) that was drum fed and held only 60 rounds, firing with a cyclic rate of 500 rds/sec...about 7 seconds of fire. It also had poor ballistics quality and would have to be employed at shorter range ( contrary to the narrator's assertion ) After that was expended, all they had were two 7.7mm machine guns.

The A6M5 arrived in 1943 and up used a better cannon that was belt-fed, allowing more fire time. It also had a slow rate of fire, but much better ballistics.

The British Hispano 20mm cannon used in the Spitfire, Tempest, Typhoon, Mossie ( and a US produced variant used in the P38, some Corsairs ) and the German Mauser MG151 used in Bf109 F and subsequent, ( and in most all other of their fighters ) were very good weapons the had a decent rate of fire, as well as good ballistics. They were heavier than machine guns and carried less rounds though.
 
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kc135topboom
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RE: Cannon Or Machine Gun?

Sun Jan 14, 2007 5:01 pm

Quoting SlamClick (Reply 22):
1. The very high velocity projectile was said to go unstable or even disintegrate when hitting foliage, making it a poor choice for a jungle war.

2. The mechanism was said to be too close-spaced and confined to tolerate the introduction of any dirt, mud, etc to the action. Read David Hackworth's account of digging an AK-47 our from under a dead-and-buried Vietcong. He fired off the entire clip on full auto without first cleaning the weapon to illustrate to his troops the weapon they were up against.

No, the 5.56mm round would not disintegrate when it hit foliage, it went right through it, just like any other bullet.

The early problems with the M-16 jamming was not the fault of the gun, or the fact it was not cleaned properly. It was the type of ammo the US Army selected. The recommended round was "ball" ammo, but the US Army selected the cheaper "stick" ammo rounds. It was the stick ammo that left deposits that would eventually jam the gun.

While it is true you can pull an AK-47 (or AK-74) out of the mud, and fire it (but I would not recommend it). The manufacturing tolerances would not allow you to interchange parts from two broken guns to build one operational gun.
 
L-188
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RE: Cannon Or Machine Gun?

Sun Jan 14, 2007 6:35 pm

Quoting KC135TopBoom (Reply 25):
It was the type of ammo the US Army selected. The recommended round was "ball" ammo, but the US Army selected the cheaper "stick" ammo rounds. It was the stick ammo that left deposits that would eventually jam the gun

Just to clairfy you are refering to types of powder. The Army changed the powder specs during the development of the weapon and it suffered for it.
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SlamClick
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RE: Cannon Or Machine Gun?

Mon Jan 15, 2007 1:08 am

Quoting KC135TopBoom (Reply 25):
the 5.56mm round would not disintegrate when it hit foliage,

Such was the in-country conventional wisdom. I'd heard the same thing about .220 Swift so I found it credible. Never tested it. Only fired my own M16 across a hundred yards from my back window into another window in town during Tet 1968.

Quoting KC135TopBoom (Reply 25):
"ball" ammo, but the US Army selected the cheaper "stick"

I seem to recall that the powder was the same as they used in the 7.62 and that the issue was not price but that the powder gave higher velocities and energy than was available with civilian .308 ammo. Anyway I agree with the statement below:

Quoting L-188 (Reply 26):
you are refering to types of powder.

* * *


Quoting KC135TopBoom (Reply 25):
The early problems with the M-16 jamming was not the fault of the gun, or the fact it was not cleaned properly

Well, for Army as opposed to Air Force personnel, complaints about cleaning issues are a pretty serious criticism. Grunts have told me that the maintenance time on the rifle exceeded the combat time; that a twenty minute firefight would necessitate a 90 minute cleaning.

What constitutes a reasonable amount of cleaning for an infantry weapon is one concept sitting around a conference table at the Pentagon and another quite different one sitting on a poncho in the mud.

We had a preventive maintenance magazine circulated in-country and I'll bet half the words published in that magazine were about care and cleaning of the M16. At the very least, one could say that it compared unfavorably with every other Army rifle of the century in that regard.

The one example I was told of one individual that never once jammed in (at the time) eight or nine months of daily firing was the CAR-15 carried by a FAC friend of mine. His trick, or superstitious ritual or whataever was that he never loaded the magazine with more than 18 rounds lest it jam on the very first firing, and he shot 100% tracer with it.
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