HI
I read somewhere that the .50 BMG is just an upscaled 30/06 and that a 222 is a downscaled 30/06.
I'm wondering seeing that the .50 BMG was arround in 1918-1920's- what was it never upscalled further to a 1 inch or a 1.5 or 2 inch shell and the machine gun that fired the .50 BMG upscalled as well to make a large caliber auto cannon.
a 1 inch BMG firing a 1400 grain FMJ or HE at say 300 rpm would have made a mess of a LOT of things during WW2.

Arming MTB's and jeeps and half tracks with a 1 inch or 1.5 inch version would have produced a powerfull quick firing cannon on a mobile platform especially in a twin unit or depending on size a quad unit.

I recently read a book about English MTB's and the first ones were armed with lewis' or Vickers let alone any sort of cannon. It mentioned PT's but only from latter in the war and by then they were listed as armed with twin .50's amid and 20mm for and aft. Is it true US PT's eneded up with 40mm twins on them for and aft by the end of the war??

What was the heaviest armed/gunned small boat of WW2?

I started to think why wasn't there any fast firing smaller cal cannons

Anyone know why there weren't any auto cannons in early WW2??

Thanks

later
P

Lots of questions here and a few errors, but I'll try to shed some light. The current US Fifty caliber MG the M-2, is basically the same weapon as when first introduced in 1927. Can't improve much on perfection.

Regarding the "upscale" of the 50 cal you ask, the answer is we DID or rather the Swedes did with the very fine 20mm (almost a 1") cannon we and the Brits used to a great extent during WWII and even today. We and the Brits armed our PT (MTBs to the Brits) Boats with single barrel 20mms and some indeed have single barrel 40mms and other various and sundry armaments, mostly it was up to the innovation of the boat's skipper. So the 20mm Oerlikon was a relatively fast shooting cannon as was the single and quad 40MM Bofors cannons of WWII which we equipped all of our surface ships with. The biggest advantage of the 20mm & the 40 over the .50 cal was the ability to shoot HE (high explosive) shells in addition to armor piercing (AP) and tracers. jorge

The simplest answer to "why didn't they...." is recoil. The Ma Duce will rock a Hummer hard and shake a 5 ton truck.
BTW, it's the 223 / 5.56Nato that's a scaled down 30-06 (not the triple duce)

They did make a slightly larger MG round, but gave up on it "before Jorge's time"


#2 is the 5.56, #5 is the 30-06, #6 is the 50BMG and #7 is the 60HMG

In the next photos, you can see what the 60HMG developed into (#2 & 3 are Russian rounds).




There is another "son of 60", the "50-60 High Velocity" which is simply a necked down version of the 60HMG (developed about 1000fps higher velocity than the BMG round).

Seems to me, the 20 mm came about because that was the smallest caliber feasible at the time to carry an explosive charge effective against aircraft. the Maxim was built as large as 37mm, with explosive shells.
Grizz

if the MA deuce recoil is so bad - how did the willys jeeps with .50's mounted on them go?? or were they shaken apart??

I say recent footage of a twin 50 setup on a willys used by rangers in the Italian campain with the break out from Anzio. seemes double trouble

What were the quad .50 AA mounts carried/used on??
The germans used a 15 or 20mm mauser auto cannon on a light trailer as an infanary weapon- was the oiliken ever used that way by the US??

THanks
later
P

The Germans equipped Aircraft with 20m and 30mm automatic cannon as early as 1939- the FW190 and it's prototypes. The Russians also used cannon. The Germans even had an airborne Pak 88.

If you look the dimensions are not direct scales of .30-06 up to .50 and down to 5.56x45. That the .30-06 and .50BMG have similar speeds with their main projectiles is what caused this myth, the 5.56 is some 250-450 fps fater than a milspec .30-06 or .50BMG ball loading.

I thought the jeeps of WWII were equipped with the smaller air-cooled 30 caliber Browning machine guns. I cannot recollect ever see a WWII jeep armed with the 50BMG. Can anyone shed more light on this?

It's not really correct to say that the 50BMG is a scaled up 30-06 and the 5.56x45 is a scaled down version. It's probably more of a coincidence that it turned out the way.

The 50 does come close to being a scaled up 06. During World War I the United States was armed principally with 30-caliber machine guns. Very much impressed with the 11, 12, and 13 millimeter heavy machine guns used by other countries, the Army obtained samples of the ammunition and proceeded to investigate possible new machine guns to handle the larger cartridges, which were mostly rimmed cases. General John Pershing insisted that much time and money could be saved by simply scaling up the Browning M1917 machine gun and making a rimless cartridge to match. No need to reinvent the wheel. Fortunately, the General's advice was followed and by the end of 1918 the Caliber .50 Browning Machine Gun (50 BMG) had been perfected. The cartridge itself was somewhat of a disappointment due to the powders available at the time but new powders developed in the 1920s and 1930s brought out its full potential.

On the other hand, the 5.56x45 went thru a series of iterations ranging from the 30 carbine necked to 22 caliber all the way to the 06 necked down likewise. The project was very nearly killed by the 7.62x51 NATO cartridge but was saved by the Air Force who were looking for a lighweight cartridge and rifle. What really determined the final cartridge shape and size was the outstanding Armalite rifle developed by Eugene Stoner. He developed the rifle based on a lengthened 222 Remington case and both Remington and Winchester produced ammunition to his specifications for testing. Those cartridges were virtually identical to todays NATO round. (boxes of both shown below)

Ray

The 30-06 and the 50BMG have the same shoulder angle and such. If you were to look at the SAAMI specs for both, you would find that they a proportionally the same case. Not really rocket science. The 30-06 is a fine cartridge, and when the military folks were looking for something a bit beefer for a machine gun, why not take the -06 case and enlarge it proportionally. Beats trying work up a new cartridge. Handloader Journal had an article a few years ago about this.

Regards,

BB

quote:

If you were to look at the SAAMI specs for both,...

There are no SAAMI specs for the .50 BMG, only NATO specs. But I do agree, the 30-06 and the .50 BMG are very much alike, with regards to shoulder angle and such.