EmericD said:

By the way, I shot last week a very sweet 5.56 x 40 mm round, with a bullet C7 of 0.208 launched at 945 m/s from a "pseudo Mk12" (18'' barrel). Hitting at long range was so easy (and fast) it was like cheating.

EmericD said:

The cartridge started it's life as a regular 5.56x45 mm M855 from IMI, we removed the bullet, saved the powder, shortened the case by cutting most of the neck...

Sounds very interesting.  So instead of going completely neckless, this time you opted to keep a very short neck.  Reason(s) why?

Also, any pics of the bullet and/or loaded cartridge?

EmericD said:

       stancrist said: When 5.56 became the US standard rifle caliber, it in effect became a de facto NATO caliber.

Not really. The US "5.56 mm" was the M193, and what became the second NATO calibre was the SS-109 familly, not really the same cartridge.

Oh, please.  Using a different bullet just makes it a different loading, not a different cartridge.

In any event, the point is that NATO adopted 5.56 only because it was a standard US caliber.

stancrist said:

Oh, please.  Using a different bullet just makes it a different loading, not a different cartridge.

I would normally agree, but since the M16A1 designed to fire the M193 was unable to fire effectively the SS-109, one can't simply consider the SS-109 to be "a different loading", as you need another weapon.

People in France once considered the SS-109 to be "simply a different loading", and tried to feed the FAMAS F1 with SS-109 ammo, the result was not really impressive.

stancrist said:

In any event, the point is that NATO adopted 5.56 only because it was a standard US caliber.

I have to disagree. If the point was just to please Uncle Sam "because it was a standard US caliber", then NATO would have selected the XM777, not the Belgium SS-109...

So you got another round of your neckless brass case done did you?

I would ABSOLUTELY love to have a stash of that for my new 11.5" not sbr!

"In any event, the point is that NATO adopted 5.56 only because it was a standard US caliber."
 

This is more of a statement about the cartridges that SS109 competed against than that M193 was already in use by the US.

stancrist said:

Sounds very interesting.  So instead of going completely neckless, this time you opted to keep a very short neck.  Reason(s) why? Also, any pics of the bullet and/or loaded cartridge?

The last on the right.

The reason was simply that we didn't planned to have such a large groove at the base of the ogive (the groove is for the plastic case version, not the brass tests), and needed to keep the residual neck out of the groove.

EDIT:

Oups

That's better

EmericD said:

       stancrist said: Oh, please.  Using a different bullet just makes it a different loading, not a different cartridge.

I would normally agree, but since the M16A1 designed to fire the M193 was unable to fire effectively the SS-109, one can't simply consider the SS-109 to be "a different loading", as you need another weapon.

No, you absolutely do not need another weapon.  You only need another barrel, one that has the correct rifling twist for the bullet.

For instance, a friend of mine once shortened the barrel of an M16A1 to 8 inches.  When he fired M193 ammo, the bullets keyholed.

I suggested that he install a shortened M16A2 barrel.  He did so and that solved the accuracy problem.  Same gun.  Different barrel.

EmericD said:

People in France once considered the SS-109 to be "simply a different loading", and tried to feed the FAMAS F1 with SS-109 ammo, the result was not really impressive.

Of course.  (See my comments above.)  That does not mean it is a different cartridge, though.

5.56x45 is still 5.56x45, whether loaded with 55gr bullets or 62gr bullets (or any other weight).

EmericD said:

       stancrist said: In any event, the point is that NATO adopted 5.56 only because it was a standard US caliber.

I have to disagree. If the point was just to please Uncle Sam "because it was a standard US caliber", then NATO would have selected the XM777, not the Belgium SS-109...

I did not say NATO adopted 5.56 "to please" the US.  I said NATO adopted 5.56 because it was a standard US caliber.

The only reason there was NATO interest in 5.56x45 was because the US had adopted and was using that cartridge.

If 5.56 had never become a US standard caliber, it's extremely improbable that NATO would have wanted to adopt it.

ramlaen said:

This is more of a statement about the cartridges that SS109 competed against than that M193 was already in use by the US.

Is it?  Do you think the SS109 loading would ever have been created if 5.56 had not been a standard US caliber?

EmericD said:

Oups

Yeah, I imagine achieving/maintaining proper bullet alignment might be problematic with such a short neck.

autogun said:

Sounds like the 5.56mm FABRL*, shown below with the M193.

Take .222 REM case; shorten neck 3mm; load Emeric's bullet = 5.56 FABRL Magnum?