21 cm R Spr Gr 4401 puzzle

[Grzesio]

There was a certain 21 cm R Spr Gr 4401 rocket apparently to be produced in late 1944, 5000 pieces per month.
It consisted of a ballistic cap drawn from sheet metal, forged closure plate, machined (war)head, body of yet unspecified technology, cast fuel support ring, nozzles machined from seamless tubes, forged nozzle plate and cast rear body.
Production problems eventually lead to manufacturing the ballistic cap of three longitudinally welded segments.

It can be clearly seen, it was not the 21 cm Wgr 42 rocket, which did not have separate nozzles or a two piece body.
There were 21 cm rockets with separately mounted nozzles surrounded by a sleeve, which could be called the "rear body" - e.g. naval 21 cm RLg or some early 21 cm Fla-Rakete, but it is clearly none of these...
So what was the 21 cm R Spr Gr 4401? Some HE variant of the 21 cm RLg? Kriegsmarine did in fact use some 21 cm HE rockets for their 21 cm R Ag M 42 launchers, but I've never encountered any closer information about them. On the other hand, "21 cm R Spr Gr 4401" is clearly not a Kriegsmarine designation.

Any ideas, please?

Kind regards

Grzesio

 

[Nabob]

Hi iI am not with my computer right now to verify, but could it be a rocket assisted projectile for 21cm gun?
Bob

 

[Grzesio]

Well, I somehow never thought about it.
I have just two slight and not decisive reservations - Germans generally designated HERA shells as R Gr, although not without exceptions (e.g. 15 cm kz R Sprgr), then the description of the projectile, as mean as it is, does not mention driving band(s).
Nevertheless it is an option really worth considering - I think rocket assisted shells seem to be a tempting choice for 21 cm Mrs 18 or so. I've done quick check in my books, with no result so far.

I also wish I knew, which armed forces branch was responsible for the project...

 

[Nabob]

Hi,
after briefly looking at my documentation I was unable to find this designation.
You are probably right with the designation R Sprgr to be a rocket propelled (spin stabilized?) projectile.
It could be used with some kind of weapon system like the 38cm R Sprgr 4581 for the 38cm Sturmmörser.
I am not able to make the mental leap to figure this out right now, I am strugling to find a system in the designation of these projectiles.
I will start a separate thread on this.
Does Your source documentation have drawing numbers for the parts (format should be 13 - D - 10311)?

Bob

 

[Grzesio]

Hi,

Yes, I was thinking of this designation system too from time to time. It seems, it was introduced somewhere in 1943, a separate thread would be great anyway.

Sadly, basically nothing more is written as I quoted above. It's not a secret source, two scanned notices are presented here, at the very end of the page: http://www.deutscheluftwaffe.de/archiv/Dokumente/web/new site/frames2/Dokumente.htm
I think now, the "11/1e" signature suggests, it was a Wa Pruef 11 development...?

Regards

Grzesio

 

[Nabob]

Sorry but the link opens only blank page wihout a document.
Bob

 

[Grzesio]

Uuups!
Corrected: http://www.deutscheluftwaffe.de/arc... Wurfgranate/21 Wurfgranate 42 Munition.html

And that's all...

 

[AE501]

21 cm R Sprgr

I do not know whether this helps, but this is what the advancing British were finding at their research establishments at the back end of 1944. Doubtless the US were doing the same but had further to go.
I saw your link and it bears out the fighter plane connection.