7,92x57 SmE core types


#1

Dear colleages!

Please, help me to understand the situation with German 7,92x57 SmE bullets.

The information of the beautifull book Brandt, Hamann, Dr. Windisch. DIE MILITÄRPATRONEN KALIBER 7,9MM IHRE VORLÄUFER UND ABARTEN, 1981 indicate that there was 3 types of SmE geschosses:
Type A - core with flatened tip, bullet with triangular cannelure
Type B - core with sharp tip, bullet with triangular cannelure
Type C - core with flatened tip, bulet with rounded cannelure.

But during inspection my collection, I was not able to found SmE bullets with rounded cannelure. I also don’t understand the differencies between type A and C Geschosses - as per BHW, they differ only by cannelures (triangular for type A and rounded for type C).

In the same time, some of SmE bullets in my collection have a flatened core with small cavity (as I show at the picture below). The depth of this cavity is about 0,5 mm.

So I have some questions, and, hope, somebody can help me with them:

  1. Did SmE Geschoss with rounded cannelure really existed?
  2. What was the differencies between SmE Geschosses Type A and C?
  3. Does my alternate solution, shown on the right side of the below drawing, is correct? May be the core with flattened tip and small cavity is Type C?


#2

According to the picture type A should be a slighty longer bullet than type C too.
I sectioned a SmE bullet today.It has a pointed core so type B,I think.There is a small cavity between between the lead portion and the point of the jacket too


#3

Treshkin,

There are two sme cores.One with a flattened tip and one with a sharp tip.
The difference of these two are that the one with the flat tip was a pressed iron core without a further handling.The core with the sharp tip was also pressed but to sharpen the tip it was necessary to drill the tip on a machine, this was expensive and time-consuming .The problem with the flat core was that the lead in the bullet was about 1 gram higher than with the sharp core. 1 gram is not much but on hundreds of millions of bullets its a lot lead.The bullet with a small cavity in the bullet is normally a bullet that held a sharp core.They tried these bullets with a flat core to reduce the lead but these bullets had a bad ballistic. In the middle of 1944 they had the knowledge to pressed a sharp core. This is recognizability on the bottom of the core with a pressline from about 0.8mm wide.

451kr.


#4

This is the bullet I sectioned today.It was pulled from a '44 7,92 x 57 with steel case
Look at the machinery signs on the point of the steel core

(sorry for the poor quality of the job,it was the first time…)


#5

A different one…


#6

There are some differences between the 2 bullets.Mine was pulled from a Hla case made in 1944.Note the machinered portion of the core and the differences about the lead portion


#7

Apparently there was a lot of experimentation on 7.9 SmE bullet cores. One of the HEC reports I have from VDM Heddernheim (cvg) as early as 1939 was testing bullets made with Sintered Iron cores, but their sintering machines couldn’t produce the sharp points on the cores so they made cores with blunt tips and used iron wire and a rivet machine to make the sharp points seperately. These bullets were loaded by hla, but it sounds like they were never more than test items. The VDM papers on SE bullet development regularly refer to sintered cores for 7.92 bullets.


#8

Thanks all for very interesting comments. This info is very important for me.
I ahve only last question. Did somebody have or seen SmE bulet with rounded cannelure?