7.65 x 21.5mm sub-calibre

Can anybody provide any information at all on this unusual Swiss cartridge? The only reference to it that I’ve managed to find anywhere is on Tony Williams’ site where it is described as being for the Erika Pak 75. Is it a tracer or just a ball loading? Would I be correct in thinking that the bullet is solid lead coloured with a brass lacquer - a small scratch to the surface reveals lead underneath the lacquer. Does anybody have a box label or know it’s designation?
Any information at all would be good!

Here you go (in Spanish):

Apparently it is a subcaliber spotter-tracer for training with the RL-83 Blindicide type launchers, which includes the Swiss 58/80 variants.

Hello Jim,

The swiss german designation for this cartridge is 7,65 mm Leuchtspurpatrone 75 für 8,3 cm Rak Rohr Einsatzlauf and it is loaded with a tracer projectile. Although it is based on the 7.65 mm Parabellum case, shoulder diameter is wider. My round has the same headstamp as yours and was taken from this box:

Fede - you mention that the shoulder diameter is wider on the 7.65 Leuchtspur training cartridge. Do you mean by design? I measured the following three cartridges from my collection the best I could, not knowing the exact point of reference for the measurement you were talking about, and got the following results:

7.65 Lsp D 4 T 74
Just below shoulder: .3765" (9.57 mm)
Just above shoulder: .3295" (8.37 mm)

7.65 Ordinary Ball D 4 T 74 (Yes, just happened to have the same quarter and year, also with blue PA.
Just below shoulder: .374.5 - .376" (9.51 mm at smaller diameter)
Just above shoulder: .330" (8.38 mm)

7.65 Ordinary Ball D D 11 T 57
Just below shoulder: .3755" (9.54 mm)
Just above shoulder: .329" (8.36 mm)

I would say that all three of these rounds would interchange in a normal specification chamber. The just seem to be in the same range of specification. Perhaps I am wrong? It is not easy to measure right at the bottom of an incline, and not so easy at the neck of these rounds, due to very deep, longitudinal neck crimps. If the caliper gets into one of the crimps, and they are big enough for that, it changes the measurement enough to be significant.

Hello John,

          Well, I don't know why I have mention that but I'm obviously wrong! I have also checked my measurements between those of the 7.65 mm Parabellum and the subcaliber case and these are not significant. Thanks for correcting me, my friend.

More information than I could have hoped for! Thank you all.

Fede - I see on the Spanish site, if I am translating it in my head correctly, that they say the bullet has a brass jacket. Do you think this is correct. It seems mine is brass-washed (or otherwise coated) lead. I have not scratched it, but it has the feel of lead, and the look of it. Am I wrong, or is the Spanish site wrong? If the latter, could you write them to correct it? As I am getting older, and since retired, do not have the opportunity to use the language much, my Spanish, including written, is getting poorer and I am embarrassed to write it to this site.

I have only seen a b/w picture of a sectioned round but it certainly looks like brass-washed lead (in its original form should also have a very sticky coat of parafin). The tracer compound is contained in a plastic cannister.

Some of the guys from municion.org are members of this forum so I’m sure they will be able to correct that mistake. The main weapon is also a rocket launcher, not a grenade launcher.

Fede - you are absolutley right about the internal construction. I’ve sectioned one of these rounds and have been looking for the picture to post, but no luck so far…