I am looking to compile information on a couple of guns we are currently working on, hopefully the boat, group or operating area that these guns would have been on or in.

What type of boats were outfitted with the 3.7cm SK C / 30 U on the L.C / 39 mount? I have a partial list below and was looking for help at filling in the blanks.

It appears that the early type IX boats were fitted with it and commonly omitted later due to the extended Wintergarten platforms being fitted to the boats.

I have seen pictures of the IX (U-66 Sunk) ,IXC (U-163 Sunk), IXB (U-108 Scuttled),IXC (U161 Sunk),IXD (U-188 Scuttled), XIV (U-461 sunk) all with SK Cs.
The IXC Type U-515 Is listed as sunk, but reported as captured on pg 233 of Gordon Williamsons book?
There is a large list of boats with 3.7cm guns, IXA, IXC/40, IXD1, IXD2, IXD2/42 listed as aft armament.
IX,IXC, IXB,IXC ,IXD , XIV , IXA, IXC/40, IXD1, IXD2, IXD2/42 All look like they had the SK C.
Other boats have the 3.7cm Flak listed. I am not to sure how often this is confused though with the SKC or the other way around.
I am also hoping that someone can shed some light on the nomenclature stamped into the rings.


They are as follows: (my notes)
3.7cm SK C / 30 U (37mm U boat Gun)

L.C / 39 (U Boat Mount)

(the rest of the markings are what I need to verify)

Eagle and Swastika
M (on left side)
B (on right side)
U (below)

One gun follows this arrangement with 1601.



It has 57847 above the Swastika /1601
It also has 639 (6 may be an 8) on top of the ring.

The other gun follows the MBU and Swastika with a 1590



Has 57847 and 516 on top of the ring.
I was told that the MB is the area of operation or group and that the following # is the catalogue #.

Any way to substantiate this or to follow the catalogue #?

Any way to identify the # on top of the ring? Both of these are Boats, but neither boat seems likely.

Both of the #s on the tops of the rings and catalogue #s were hand stamped after the gun had been factory marked.



These guns were put into service for the Spanish navy on the Dedalo (USS Cabot Independence Class Aircraft Carrier) post war and then the ship was scraped back in the US after leaving Spanish service. The guns would have been in Spanish inventory post war. Since the guns were largely considered obsolete by 1942 they may have been on boats used in the Spanish conflict prior or during the war by the Germans or Spanish boats.


I am hoping someone has records or contacts in reference to the markings or history of these guns.


These guns came out of Spain post war. But it seems that the Type 1(E1) project did not have the 3.7cm gun on it.

Was there any retention of U-boats or Germen armament by Spain after the war?

Thank You
Ira