7.9mm Blank question


#1

This question is for John Moss (or anyone else who might know!)
John – I got this blank from you at SLICS. I think you told me they were made by H. Huck in Germany using any available cases, but I’ve forgotten what you told me was the purpose of the round. Was it an attempt to make extended, full length blanks out of regular cases or something else?


#2

Phil - it is definitely a Huck Blank, on an Iranian case (Probably a contract case for Iran rather than made there). I don’t know why it was designed the way it was. It seems like a hard way to make a blank, with that added shoulder and neck. The booklet on Huck products shows it, but there is no special explanation about the design.

Sorry I can’t be of more help. Maybe one of our friends in Germany knows why this design was made. I think they exist in 7.62 x 51 mm also, but I could be wrong about that. I am almost sure, though, that I have seen one in some other caliber besides 7.9 x 57.


#3

Hello Phil,

This patent may help you to get an idea about how this blank cartridge is constructed:


#4

The Case is an Iranian 7,9 1950/1951 date case ( Persia/Iran uses the Hegira Year (different from Turkey) 621.5 CE (July) ) for its dating system.

The over-the-shoulder sleeve is a very “iffy” method of making blanks with an extended profile, as this sleeve can separate in the chamber and cause all sorts of problems, unless soldered in place.

Whilst it will not “go down the bore” on firing, (due to the “shoulder”) it can “come loose” due to Gas re-circulation on firing.

The Initial British .303 Blank back pre-WW I, with a crimped-inside-the-neck sleeve was also withdrawn for this “profile shedding” propensity…the profile going down the barrel and acting like a bullet ( although hollow and sheet metal fragments)

WE make “Long” Blanks by expanding the neck of a case to .400, then slipping in a .375 (3/8ths") Thinwall (.014) Brass tube, all the way to the base of the case, then RESIZING the Case-And-Tube together, to form an internal liner, which is locked in by the case shoulder, neck with crimp, and the projecting “profile” which is then reduced to under “bullet” diameter, for proper feeding. The final star crimp completes the Blank. (Constructional details)

As to why Huck got the cases from Tehran Ammo Factory, that is a conundrum. In 1950, (West) Germany was still under Allied control and Supervision, so any supplies of ammo for the Internal Police Forces would have been quite strictly controlled. The Army (Bundeswehr) was not reconstituted till 1955 or so.
And all the (pre1945) Ammo factories had already been effectively dismantled, destroyed or given away.
So a Foreign source of cases, at least, had to be found. Whether they were Once-fired cases bought as scrap, or new cases is unknown from the Photos. The three stab crimp is typical of both German and Persian cases ( Tehran Factory was equipped by ZB in the 1930s); there doesn’t look to be more than one set of crimp marks, so are they “new” cases, or even “Pulled down” Ball ammo? or a batch of Persian ammo/cases without crimp to start with?

Ahh, the questions that the lack of a Paper trail bring up!!!

Regards,
Doc AV
AV Ballistics Film Ordnance Services


#5

I would say that the case has been previously fired. There are typical bolt face markings on the case head and it has been reprimed. The 3 stab crimps have been smoothed out and no longer cover the new primer.


#6

Any chance that the Iranians played with the Huck patent?


#7

It seems that there is no coincidence that many Huck remanufactured cartridges were made from FN cases and these iranian cases from 1950 are also an FN product.


#8

Jonny - I would say that there is little to no chance that Iran made any of the cartridges covered by the Huck designs. I knew this case was not actually made in Iran, although I didn’t know for sure it was made by FN. Fede is correct that Huck also used many FN-marked cases, as well as some others. In their pistol blanks, etc., one finds the use of a lot of Italian and Spanish cases, for example.

Fede - the patent drawing is very nice and interesting. Thanks for posting it. However, without the text, for someone not into cartridge engineering (me), it doesn’t tell me too much about the “why” of the case design. Coupled with Doc Av’s remarks, I can mention that on these Huck blanks, the sleeve comprising the shoulder neck and extension are often found split, so that it appears that while these are interesting collection pieces, they were a poor design.
It sould probably take the entire text of the patent for many of us to understand all of the ramifications of the design of this particular blank.


#9

John,

   Here is the full text:

   [img]http://i381.photobucket.com/albums/oo255/FEDE_EL_SOMALI/3-10.jpg[/img] 

   [img]http://i381.photobucket.com/albums/oo255/FEDE_EL_SOMALI/4-8.jpg[/img]   

   [img]http://i381.photobucket.com/albums/oo255/FEDE_EL_SOMALI/5-4.jpg[/img]

#10

Wow, Talk about “Ask and yee shall receive”!!
Thanks to all for your input and information.


#11

[quote=“DocAV”]The Case is an Iranian 7,9 1950/1951 date case ( Persia/Iran uses the Hegira Year (different from Turkey) 621.5 CE (July) ) for its dating system.

The over-the-shoulder sleeve is a very “iffy” method of making blanks with an extended profile, as this sleeve can separate in the chamber and cause all sorts of problems, unless soldered in place.

Whilst it will not “go down the bore” on firing, (due to the “shoulder”) it can “come loose” due to Gas re-circulation on firing.

The Initial British .303 Blank back pre-WW I, with a crimped-inside-the-neck sleeve was also withdrawn for this “profile shedding” propensity…the profile going down the barrel and acting like a bullet ( although hollow and sheet metal fragments)…

Regards,
Doc AV
AV Ballistics Film Ordnance Services[/quote]

Just to add a few notes on blanks with separate mock bullets, and to clarify a little on DocAV’s remarks.

The .303 blank that Doc is refering to is the “Cartridge Blank .303 inch Cordite with Mock Bullet Mark VI”, and of course was not the initial .303 blank, that having been the rolled case Mark I. There had also been three marks of black powder and five marks of cordite blank prior to the Mark VI.

The Mark VI blank consisted of a normal rosette crimped blank with a mock bullet made of thin sheet brass crimped over the neck, not inside. The case was blackened for identification. It was introduced in December 1901 but by 1904 reports were being received of the mock bullets remaining stuck in the barrel and of live rounds being mixed with blank. Never a good idea!

In 1906 the Royal Navy removed the mock bullets and the army followed suite in February 1907. The round then effectively became like the preceding Mark V blank but was now titled “cartridge SA Blank .303 inch with mock bullet removed Mark VI”

Pictures show bothe versions of the Mark VI Blank.

The idea was not new though. The final picture shows a very early British .303 blank, probably dating from around 1890, with a rolled case covered in cardboard and a brass mock bullet. presumably this was tried as an answer to the problems of using the short stubby rolled case .303 blank (shown alongside) in a magazine rifle.

Regards
TonyE