Colour of german 7,9x57 tracer


#1

Did an experiment today. Had a number of very corroded steel cased german SmKL-spur and instead of chucking them I built a setup for igniting the tracer. Well the tracers did not light properly, only made a couple of feeble spurts, probably corroded too, but the colour was definitely green.
Setup was old heavy vise for the bullet and a long gas/air soldering burner turned down low, welders mask and gloves. Tested it on a modern swedish 7,62 NATO tracer bullet and got a nice ½ foot long bright red flame for about a second.
Can any of you 7,9 collectors confirm that eba Vx1 26 40 headstamp has a green tracer colour? From a box label for example.
Soren


#2

The label says it is a yellow (gelb) trace.

Photo courtesy Dutch


#3

Yes it certainly does… wonder were the green came from, maybe the copper washing of the case.
Soren


#4

Of other color exist

Grünrot = green-red

Orange= orange

A+
p-j


#5

I’ve read that the germans made the tracers in different colours to be able to tell two or more gunners’ fire apart, they certainly did in 20 and 37 mm, where for example the cruiser “Nürnberg” which often docked in Copenhagen, used different colours to tell their 20 mm Vierlings apart. I have collected pictures of box labels for some time and the favorite colour seems to be yellow, orange, red and green/red in that order. The sample I’ve collected cannot be conclusive in any way, so pure green tracer probably does exist in 7,9 mm even if I haven’t seen a box yet…
Soren


#6

Mausernut,

A thought on your yellow tracer burning green: I have no idea what the German’s used for tracer compositions, but some yellow burning star compositions use barium (nitrate) as well as sodium (oxalate). The barium gives green color and the sodium tints it to yellow. The sodium oxalate is known for it being more prone to moisture problems than the barium salts and also that its decomposition messes with other components. Don’t know much about the details of the chemistry, just thinking that maybe the yellow component had moved on to something else leaving some green component left in a marginalized composition. The results being a sputtering green flame?

Oxide of copper (perhaps from the bullet breaking down) would also lend a bluish-green flame if it came into the mix as you suggested.

Was the orange tracer exclusive to the tropical loading (if I read the box shown as [trop] correctly)?

Dave


#7

The German tracer had the following mixtures.

Red:
42,5% Strontium Nitrate
17,5% Strontium Peroxide
27,0% Magnesium
3,8% Iron Lactate
9,2% Pine Resin

Green:
25,0% Magnesium
65,0% Barium Nitrate
10% Shellac ( or Pine Resin )

Yellow:
32,5% Magnesium-Powder
12,0% Sodium Carbonate
45,5% Barium Nitrate
10,0% Ersatz Resin


#8

Unfortunately the German listings I have seen of tracers, colors, compounds etc. sort of lump all types of ammo together. Some colors were used in one type (caliber) and not used on others.

Here are the colors I have seen on 7.9mm box labels:

Gelb - Yellow
Orange - Orange
Grünrot - Green to 500 meters then red
Weiß - White

If anyone has a 7.9mm label that shows any additional color I would love to see a scan of it.

DaveE
Never checked that out before but no, the orange trace wasn’t restricted to just the tropical loading, but I noticed that all the tropical labels I have or have seen show the orange trace. Whether or not there were other color tracers in the tropical loading I don’t know, I have only seen the orange trace.


#9

Torben,

Thanks for that interesting info. I think that is the first I’ve seen of any actual tracer compositions from any county.

Phil,

Thanks. Was wondering if the “tropical” application may have required modifications to the tracer composition to ensure function with ambient conditions in mind. Orange color flame can come from modifying a red composition. Low grades of strontium carbonate with excess residual sodium in it (from precipitation during manufacture) is a culprit in making nice deep reds more orange. Being that the carbonate is less sensitive to moisture than the nitrate of strontium, I was thinking maybe it was used for the tropical loads to deal with the strenuous environment issues and resulted in an orange trace. On the other hand, it could just as well have been done by intent…

Dave


#10

[quote=“Torben”]The German tracer had the following mixtures.

Red:
42,5% Strontium Nitrate
17,5% Strontium Peroxide
27,0% Magnesium
3,8% Iron Lactate
9,2% Pine Resin

Green:
25,0% Magnesium
65,0% Barium Nitrate
10% Shellac ( or Pine Resin )

Yellow:
32,5% Magnesium-Powder
12,0% Sodium Carbonate
45,5% Barium Nitrate
10,0% Ersatz Resin[/quote]

Does anyone know the composition of “Ersatz Resin” as stated for the yellow trace?

Cheers,

M


#11

Magpie,

Perhaps “Ersatz” means “substitute” in this case? I don’t recall seeing that used in reference to a particular binder for compositions. Binders can often be substituted without much change in performance and are often used based on availability.

Dave


#12

In the German language formula it says – “Harz (oder Ersatz-bindermittel)” which translates something like “resin (or artificial binder)” [I think!!]


#13

Torben,
your list of compositions is a worthy information, but I’m standing here helpless in the middle of English and German terms. Is “Resin” translated or is this the originally used German expression?


#14

Hans
“Resin” is the English translation of the German term.

Röt - Red:
Harz als Bindemittel - Pine Resin

Grün – green
Schellack oder Harz - Shellac (or Pine Resin)


#15

My confusion is on the yellow composition. What makes me quibbling is that I was wondering if the “Resin” used there was a brand name or trade mark for some kind of resin/Harz. Then it could make perfect sense to alternatively use a substitute/Ersatz for a product unavailable named so. If the originally used resin was unsuitable there would be no reason to list Ersatz, then you give the new component name.
Does it say “Ersatzharz” or “Harzersatz” there? Substitute resin (another resin instead of the one in the original composition) or substitute for resin (wax or else instead of resin)?
The miracle to me is the necessity to replace pine resin with another material. Pine resin is a natural resource collected from pine trees, with minimal effort. Tree maintainance and collection of resin can be done with low skill labour and at invest almost zero. So far not a lot of surprises. Pine is mainly grown on sandy grounds in Europe and the further north and the further east you go, the more you will find until you reach climatic limits. So pine resin could have been a plentiful resource at that time. Germany was so much bigger then to the east, but there were even much more pine trees accessible in the occupied territories. So where is the reason to replace it? Was it technical in the end?


#16

Hans
You are way over my head in both the German language and chemistry!! The information I was quoting is on page 135 of “Die Miltärpatronen Kaliber 7,9mm – ihre Vorläufer und Abarten”. For the “gelb” tracer mixture it states “"Harz (oder Ersatz-bindermittel)"
Beyond repeating what the book says I’m afraid I can’t help much as I just don’t know.


#17

Here is the page with the tracer mixtures:


#18

Phil,
don’t tell me you are helpless in German! :-) Now I understand better. Seems to me as if this part of book translation is a bit inapt.
Harz als Bindemittel = resin as a binder
Harz (oder Ersatzbindemittel) = resin (or substitute binder)
Harz-Ersatz (better German is “Harzersatz” in one word) = substitute for resin
Looks as if they really needed to replace the original composition resin, but was it really that of pine? And again, substitution for availability or technical reasons? Anybody any information?


#19

Hans,

This may be a reach and due to my total lack of understanding of the German language, just plain wrong, but…

A very useful and popular binder for pyrotechnic compositions is Red Gum (Acaroides Resin) and is from trees that I think are native to Australia. When Red Gum is not available, a synthetic resin (trade name “Vinsol” Resin) can be used according to more modern literature I’ve seen. Could “Ersatz” be used to mean synthetic?

I think Vinsol Resin is derived from pine (which the Germans would have) and if Australia was the source for Red Gum, that could have been in short supply.

Dave


#20

Tony,

I herewith absolve you from lack of understanding the German language, my understanding German language is also far from being perfect and we kind of sit in the same boat.

This in my understanding is not forcedly implied. No matter what the original resin was, the Ersatz could be natural or synthetic, the expression allows this.

Yes, if Red Gum was used, that would have screamed for an Ersatz at that time. I’d assume they didn’t make the country rely on imports with levity, so in my opinion Red Gum was never part of the original recipe: the world was not as globalised then as much as we are today and the home of Red Gum was part of the other Empire! And too faaaaaar to conquer!