Short and long


#1

Samples: 7.92x61 Noruego and 6.5x55 mm Krag Noruego
Bullets of Norway. Short and long, bullets with what it is connected?


#2

What do you mean by “connected”? I am afraid, it is not clear what your question is.


#3

Sorry for my bad English. :(
I meant. Why some bullets short?


#4

Firstly, it is almost impossible to tell if one of those bullets is shorter (or longer) than another, without an X-Ray of the cartridges to see the position of the base of the bullet, or without pulling the bullets for direct comparison. Those are certainly not new cartridges, and over the years the bullet on one of them could have been pushed back into the case farther by some outside action. There is a way to tell the approximate bullet weight with a magnet, if the bullet have a steel jacket or a magnetic core, but the magnet must be powerful enough to detect the bullet within the case while it (the magnet) is being run down from the neck to whatever position on the case that there is no longer any magnetic “pull.” I consider that a pretty unreliable test, because the magnet. But, if the magnet is too powerful, it may continue to register even though it has passed the base of the bullet inside the case. A very delicate balance, and one that makes this test a bit unreliable.

That said, different bullet weights can be seated to different seating depths in the same case type, making some cartridges longer than others in their overall length. A lightweight bullet will generally be shorter than one of heavier weight. Dramatic differences in bullet weights, say the difference between a 100 grain and a 120 grain bullet, can general be detected by simply weighing both cartridges.

Of course, in many bolt action repeating rifles, the magazine system may or may not be tolerant of too much difference in overall cartridge length. As long as the longest cartridge is not over-length to fit into the rifles feeding mechanism, most Mausers, Mannlichers and the like are fairly tolerant of differences in overall cartridge length. Of course, this works best if all cartridges (with their bullets) to be considered are loaded and in their original state. If some are loaded and some inerted, than there is the weight of the powder charge, or its absence, to contend with in any comparison.

Not a definitive answer to your question, but about the best one can do without seeing the bullets outside of the case (or within, in an X-ray photo.


#5

Makes me sad to see 7,92 x 61 mm Tung ruined like that. Important part of Norwegian history.
Aeron, can you measure the overall length of the 7,92 cartridges? I can compare with my live examples, if want me to.

Can it maybe be explained with that these rounds obviously were emptied of powder at one point?
It seems to me they could have been seated incorrectly after pulling the bullet and reinserting it.

  • Ole

#6

7.92x61mm was produced for Norwegian M29 machine gun. And, if I understand correctly, it is the only gun to fire this calibre. Why to develop 7.92x61mm, why not to use 7.92x57?
Ole, I assume you refer to the large holes. In Russia, the bigger the hole the better it is to prove deactivation and not to have police on your back.


#7

The Different exposed Projectile lengths are due to different design or type of Bullets. In the 6,5x55 Swedish-Norwegian cartridges (M1894) the central one looks like a commercial Soft Point (156 Grains, whilst the outer two look like Military Full metal Jacket (160 grains).
With the 7,9x61 Cartridges (Made especially for the Norwegian M1929 Browning Water-cooled Machinegun (Copy of the USA M1917A1), the Central cartridge with the Longer Bullet looks like it might be a “special” type, such as an AP (Armour Piercing) Projectile. ( similar construction to the Soviet BZ-32 type projectile).

IN answer to the question about why not make the BMGs in 7,9x57 (German) Caliber, the Germans did just that in WW II, with Captured Norwegian Guns, changed the Barrels to 7,9x57, and used them on the Eastern Front for Railway Protection usage, on both structures and rolling stock (Photos from Deutsches Reichsbahn Archives).

The 7,9x61 is a very collectible cartridge, even if deactivated. What are the Head-stamp Markings?

Doc AV


#8

Norway adopted the 7.9x57 for MGs in the 20s and then later ,30s, developed the 7.9x61.


#9

Vlad;
Yes, referring to the holes. I’d pull the bullet and empty the case before drilling holes into it. Not sure what was the case (!) with these.

Doc AV;
We had Colt mitraljøse mod. 1929 in both 7,92 x 57 mm «lett» and 7,92 x 61 mm «tung».
As far as I know, there are only four cartridge types developed for 7,92 tung. Ball, tracer, wood blank, and dummy. I have the former three in my collection and the ball and tracer rounds are near identical in length. The difference is not nearly as big as the one shown in the photo that Aeron posted.
I’m going with John’s theory about them getting pushed back by accident, or my own idea of them being pulled for emptying, then seated incorrectly afterwards.

  • Ole

#10

I thought I should mention that the spelling «7,9» should not be used for the 7,92 x 61 mm, it is incorrect as it was designated «7,92» by both Kongsberg, Raufoss and the Norwegian army.
Therefore, one should use 7,92 x 61 mm instead.

  • Ole

#11

Look at the 7.92x61 from the perspective after WW1: long range machine gun fire was expected to play an important role in a future war.

That thinking caused some armies having 6.5 mm cartridges to introduce very powerful cartridges around 8 mm calibre: the Dutch changed their 6.5 mm Schwarzlose MGs to a rimmed variant of the German 7.9 mm. Sweden, Norway, and Italy introduced new designs like the 7.92 x 61 shown here.
Other armies chose to adopt a powerful long range version (heavy boattailed bullet instead of light bullet) as standard for BOTH, machine guns and rifles: U.S. .30 M1, German 7.9 mm sS, and Finland the 7.62 x 54R with the D166 bullet.
Some armies introduced a heavy bullet variant of their cartridge especially for machine gun use: D in the Soviet union, D in Poland (7.92), 32N (7.5) and 33D (8) in France and a number of others.

Alas, in WW2 mortars could fulfill this role much better and the special machine gun cartridges were dropped. (The U.S. already did it in 1940 with the .30 M2.)

Edit: Sorry for switching the French calibres: 8 mm is 32N and 7.5 mm is 33D.


#12

!!
JohnMoss, your presence here, is honor for me.


#13

All cartridges are inert.
This is not the only example of 6.5x55 mm Krag Noruego short bullet. Please. Take a look at these pictures:


Acute bullet has a steel shell.



#14

In 7.92x61 Noruego bullet pull impossible look at these pictures:





#15

tennsats, I made measurements. tennsats compare them with their cartridges. Please.




#16

7.92x61 Noruego и 7.92x57 Mauser



#17

Aeron -
I will get measurements of live cartridges (ball and tracer) and post them here.
I assume the numbers next to the bullets are the calibres. Will try to get those included as well.

  • Ole

#18

You’re absolutely right, it is the caliber.
tennsats. Thank you, I’ll wait.


#19

Aeron,

I have measured my ball and tracer cartridges.

Ball:
83,95 overall length
8,10 cal
Tracer:
83,10 overall length
8,10 cal

These are just approximate readings; I’m sorry I cannot provide more accurate measurements, my experience with calipers is simply too short for me to work them reliably.
A friend of mine will measure his too and those will be more precise
Hope it will be a bit helpful.

  • Ole

#20

Here are my friend (username 762x51)'s numbers:

Ball:
83,66 mm length
8,10 mm Ø
Tracer:
83,02 mm length
8,09 mm Ø

Here is a picture of the measured cartridges:

C уважением,
Ole