Oddball Case !

[Chris 42 RQ]

Here is one for the experts on the forum.
This item has me completely baffled, I have been told that it is one of a few thousand made for a specific purpose but that is all the information I was given.

Any light you can throw on this would be appreciated.

Case has a standard headstamp of TW 43 and measures 104.2mm long with a calibre of approximately 10mm and I should add that it appears to have been a standard 50 cal case except for the longer length.

Chris :tinysmile_shy_t:

 

[TonyE]

Odd case

Hi Chris

An interesting case, what is its provenance?

Two possibilities, neither of which seem likely though.

Around 1942/43 the US were playing with high velocity experiments at Frankford Arsenal based on the .50 BMG case. These were the T5 series and the T5E1 was a .50 necked to .30 using a very long tapered neck as in your case. The only problem is that yours is not a .50/.30!

The other is that Britain conducted a series of taper bore experiments based on the Gerlich and Janacek principles in the pre WW2 period, using ,5 Vickers and .55 Boys cases in calibres between 9 and 11mm. These continued during the war with 20mm and of course the 2 Pdr Littlejohn adaptors. However, apart from the date being wrong, I think it unlikely that the .50BMG case would have been used for this.

Do you have any other info about your case that might narrow things down?

Regards
TonyE

 

[Chris 42 RQ]

Oddball case.

Hi Tony and thank you for your theories.

I have measured the case and the base dimensions are that of a standard wartime issue 50 cal cart.
I was told that it was circa 1950 using either wartime stock which was either modified or previously modified stock left over from the war ????

Chris :tinysmile_shy_t:

 

[TonyE]

Burney

I suggested to Chris that this case may possibly be connected with the experiments conducted around 1945-47 using the recoiless principle designed by Burney. These were tried in both small arms and of course the larger calibres like the 3.45". There was also a 20mm shoulder fired weapon.

The initial SAA trials were with a long case necked to 6mm, and I have an unfinished one of these in my collection that originally came from Kynoch.

It is shown with a .303 for comparison.

Subsequently the calibre was increased to 7mm and the case shortened. The propellant was held in a clear celluloid bag and the case drilled in to allow gas escape through the venturi. Some cases were maded as two piece cases with the two halves screwed together.

The bullets were exceptionally long for the calibre.

Picture shows both types of case and an undrilled one.

Projectiles.

Of course, none of these small calibre types ever saw service but the 3.45" recoiless gun did in limited numbers.

Regards
TonyE

PS I should add that the 7mm photos are not from my collection!

 

[Chris 42 RQ]

Rare items.

Very nice items and also very informative Tony-thank you for showing those very rare items.

Chris :tinysmile_shy_t:

 

[SG500]

Hi Chris, Tony refers to the T5 .30/.50 so I've attached a picture just for comparison purposes.
The photo shows:

.55/303X99B Boys training round (headstamp K 37)

10X108 XM277 (headstamp FA 61) Head diameter is the same as a standard .5

7.62X119 This is the 30/50 T5 (no headstamp). Head diameter is the same as a standard .5 (Tony please correct me if I'm wrong here - I don't know if this is a T5 or a T5E1 but am aware that the head diameter and length of case are the same for the 2 sorts)

12.7 X 99 just shown for scale

Clearly the XM277 is the correct calibre but looks nothing like the case you have.

All INERT and perfectly legal to own.

Hope this helps.

Dave.

 

[TonyE]

Experimental

Hi Dave

Very nice rounds. The one you have is the T5, the T5E1 had a very long tapering shoulder that started about half way up the case.

In case any of the big bore guys are not aware, the .55 Boys necked to .303 was not an attempt at high velocity, rather the opposite. It was designed to reduce the danger space so that the Boys rifle could be used on ordinary .303 ranges for practice. Although the Boys manual mentions the .303 barrel for training, it never entered service.

The .303 necked to .22 that was produced in the late 1920s for Vickers and Lewis guns with .22 barrels was designed with the same thing in mind, except this was to be used on indore 25 yard .22 ranges in barracks. The final version used a lead bullet with copper gas check. It also never saw service, perhaps because of expense.

Picture here.

There was an attempt to make a high velocity round from the Boys in Canada around 1942, but it was by necking it to 7.92mm. I have never seen an example in the UK but I have a copy of the drawings. Part of this experimental series in Canada was this .303/.22 made at the University of Montreal, who were carrying out experiments on behalf of the military.

Another high velocity hybrid round is the .450 Express necked to .303 which was used for testing armour plate. I have an example but need to photograph it and post the picture later.

BTW Dave, is your .55/.303 just headstamped "K 37"? My example is headstamped "K.37. 7416AW" which is the original drawing number for the .55 cartridge.

Regards
TonyE

Perhaps I should say all live AND perfectly legal.

 

[SG500]

Hi Tony, thanks for the info. You too have some nice rounds there.
The headstamp on my Boys is "K.37" and nothing else so is possibly not quite as desirable as the ones with the drawing number on them - it'll do me though as I usually only collect rounds of over 19mm but do have a bit of a weakness for necked down rounds (I've got all sorts of 20mm that are necked down).
Dave.

 

[Chris 42 RQ]

Many thanks !

Hi Tony and David many thanks to both of you for showing us all those very collectable items.

Pity that we all seem to have drawn a blank on the .50/10mm but there are so many experimentals around that no one has even heard of them as they still pop up now and then which is reassuring.

Chris :tinysmile_shy_t:

 

[TonyE]

Hi Tony, thanks for the info. You too have some nice rounds there.
The headstamp on my Boys is "K.37" and nothing else so is possibly not quite as desirable as the ones with the drawing number on them - it'll do me though as I usually only collect rounds of over 19mm but do have a bit of a weakness for necked down rounds (I've got all sorts of 20mm that are necked down).
Dave.

Hi Dave

Do you have an example of the 20mm Littlejohn or the 20/15mm?

I would be interested to see any of your British 20mms.

Regards
TonyE

 

[SG500]

Hi Tony, I posted a reply titled "very very little john" on 21 Oct 08. Now sure how to link to that one but if you use the search function you will see a few on there.
Dave.

 

[spotter]

here you are...
http://www.bocn.co.uk/vbforum/very-very-little-t20361.html?t=20361&highlight=littlejohn

 

[SG500]

Thanks Spotter.
Dave.

 

[TonyE]

.450/303

As promised, here is a picture of the .450 NE necked to .303. It was developed in the 1935-36 period to be fired from modified P.14 rifles to assess the penetration against armour plate. This was in connection with the design of a potential new .303 rimless infantry cartridge to be used in a converted P.14. Although WW2 stopped the development of the new rifle and cartridge, I believe the .450/303 continued to be used as a plate test cartridge throughout the war.

Looking through my files of Ordnance Board Proceedings I discovered that the requirement for a high velocity .55/7.92mm round that I mentioned was developed in Canada actually started as a British requirement in 1940.

Perhaps it was handed over to Canada to develop? I will try to find out more.

Regards
TonyE

 

[Tony Williams]

Subsequently the calibre was increased to 7mm and the case shortened. The propellant was held in a clear celluloid bag and the case drilled in to allow gas escape through the venturi. Some cases were maded as two piece cases with the two halves screwed together.

The bullets were exceptionally long for the calibre.

Picture shows both types of case and an undrilled one.

Projectiles.

Of course, none of these small calibre types ever saw service but the 3.45" recoiless gun did in limited numbers.

Regards
TonyE

PS I should add that the 7mm photos are not from my collection!

Great pics, Tony, I wouldn't mind one of those....

Are you sure that the gun for them was recoilless? I have a vague memory niggling at me that the perforations were to allow the gases to expand into a larger chamber to give a kind of high/low pressure system, for extra efficiency, but I could be wrong.