Enigma in the U.S.---9mm 158 gr FMJ with Nato Head stamp

A 9mm load with a Nato head stamp, the grain is 158, and velocity is 950 fps.

Information on this round is practically (if not completely) nonexistent in the United States. I would like to know a little more about it. Any information would be appreciated. History, pressure, penetration, and common use.

I would like to know if it is safe to use in common service pistols.

Any info would be much appreciated . . .

This is a subsonic round designed to shoot with suppressed weapons.
Due to the low velocity, it is necessary to increase the weight to have some efficiency on a live target.

The common subsonic loadings for 9 para use 147 and 158 grains bullets.
The most common rounds with a 158 g bullet are the israelian ones. You can recognize them because they have a blue tip.

Regarding the use of such ctges (158 grs) in handguns, I don’t like that very much.

I shoot a lot (about 3000) of subsonic rounds every year in my Beretta 92 but they are 147 grs bullets.

About 158 grains bullets, I did it, but only for tests, because I don’t think the 92 F (and it is worse for a lot of other guns) was designed for a extansively use of ammo having a such increase in momentum.


Aqeous - it would be good if you had given the complete headstamp, which would be of interest to all who study the 9mm cartridge. Many companies have made subsonic 9mm with heavy bullets, but as Jean-Pierre said, with the 158 grain I think the most common are Israeli Military Industries (IMI) and Fiocchi (GFL).

These rounds have had some use in the U.S. with special operations personnel, mostly in forms of the HK MP5SD submachine gun.

Because of its good performance for self defense, the 147 grain is very popular as a pistol round with no consideration of use with silencers. That is the weight I prefer to carry in my Browning GP.

It would be nice if you could post a picture of the round, to include the headstamp and if you have it, of the box, Or at least tell us the complete headstamp and other characteristics of the cartridge, such as any tip colors, or colored neck and/or primer seals. all of this is of interest to 9mm fans.

I think it is the same cartridge described in another topic of this forum ( page 2 ).
This round has been discussed on an italian forum too:


I have to run to work . . . but I will have the full headstamp and pics by the end of today . . .

The link provided by Pivi is in fact the same projectile. The case has the same primer seal and the color of the brass is the same. The round in question has GFL on it, 05 for the year and the NATO cross. Fiocchi was who made it.

If anyone has the information, I would like to know how much penetration these rounds have in comparison to more conventional rounds. Actual numbers would be superb, but an objective comparison would also be very much appreciated.

I also would like more opinions on whether or not these rounds are safe fired out of pistols. Opinions/facts on chamber pressure and loading would also be appreciated as well. Also, I would like to know if anyone (or if it possible) to reload this brass to NATO spec.

Aqeous–Yes, it is possible to reload any cartridge to any level of an existing load. However, we do not allow reloading data on this forum for liability reasons. There are lots of other forums on the internet that specialize in reloading data. I suggest you go to them for actual reloading advice. You CAN discuss performance, etc. here, but not actual powder charges to use, etc.

I understand . . .

Any performance data would be very much appreciated . . .

These cartridges were reportedly made for the US Navy SEALS. I know that GFL has previously made 158 gr subsonic loads like this for the US Special Forces (early 1980s as I remember), also with a military headstamp. At that time I understood they were made for use in silenced pistols. I know the lab where I saw them (and picked up a couple) was firing them out of a pistol. The SEALS, as far as I know, still have silenced pistols and the box has no markings to indicate restricted usage, so I have to assume they are intended for pistols-at least the pistols the SEALS use. 9mm Para ammunition has very seldom been made that was not intended for dual use in both pistols and machine pistols (SMGs).

These are my thoughts but of course I don’t have the specifications that would have been on the contract, nor any technical data on the rounds so I can prove none of this.

an undated Fiocchi (Italy) Catalog entitled "Sproting and Defense Ceterfire Ammunition) gives the following information on the 158 grain subsonic 9mm cartridge:

Bullet: 10.24 grams/158 grains
Muzzle: 300MPS
V@25M: 290MPS
V@50M: 275MPS
Energy (juoles):
Muzzle: 460
E@25M: 430
E@50M: 387
Trajectory: (I am assuming that this measurement is in millemeters)
25M: -35
50M: -145
Test Barrel: 200 (Again, I am assuming that this measurement is in millimeters, so it would replicate about an 8inch barreled SMG)

I’m sorry that I didn’t look all this up originally. Sometimes I have a time problem while working on the forum.

Thanks . . .

Muzzle: 300MPS

Just a quick note for the fps aficionadi.
it is 300 meters per second (300 m/s) = 985 fps.
330 m/s (1085 fps) being the sound velocity in the standard conditions.
300 instead of 330 means they keep a margin to have no problem when the temperature changes.

Test barrel 200 mm : 8 inches.
This is a SMG barrel.

Conclusion : this round must have a very poor efficiency if shot in an handgun with a barrel of 125 mm (5 inches)
It is underloaded.


I dont think it is for using it in a MP5K.
It would be a disaster because the velocity would drop moer because it uses a ported barrel.
Specifications like that are for using with a standard suppressed SMG, not one having holes in the barrel

I said I thought it might be for use in the MP5SD because so many special operations forces throughout the world use it, including U.S. Navy SEALS, and it is thought that some of this Fiocchi NATO-Marked ammo was originally made for the SEALS, although no documentation to prove that assertation is known. I don’t know of any of these silencer loads with very heavy bullets that have impressive ballistics. Of course, by the very definition of them, SUBSONIC, the velocity will be low. Also, there is only so much velocity you can get out bullets of this weight in small-case-capacity cartridges like the 9mm without encountering excessive pressures for any arm built for this caliber. Still, they seem to do the job and I would not want to be shot with one anywhere not protected by body armor even from a pistol. (Hell, I don’t want to get shot with one even IF protected by body armor!)

Of course, they may never have been intended for use the MP5SD. I have not studied silencers much, because i have no personal interest in them, and never had any professional interest in them since they are largely illegal in all of the united States, and expecially so in my state, where it harder than most places to get permits for these kinds of weapons.

I was around units issued with MP5SD’s from 1983 to 1989 and they were never used with subsonic ammunition, nor were the Mk 11 S Stens or the L34A1 silenced SMG’s any 9mm subsonic ammunition was used with silenced pistols. Even the 9mm Welrod used standard Ball ammunition. This was quietest handgun I ever fired. Beating IMO the silenced .22 RF pistols using subsonic.

Just by 2 pence worth. ;-)

I don’t know how you call the different MP5 SMGs.

You have the regular one (with no intergral silencer) and the special one (with an integral silencer).

  1. With the first one you must use subsonic rounds when you attach a sound suppressor.
    The optimum will be : the heaviest bullet going just below the sound velocity.
    it gives : 158 grains, 1000 fps

  2. about the second one. (you must call it SD I think).
    This gun, like the silenced Sten, like the 22 High standard, like the 32 ACP Welrod, aso, use standard ctges (supersonic).
    (125 grains bullets for example)

In order to get a sub sonic velocity at the exit, they drill holes into the barrel (ported barrel)
Pressure is therefore decreasing, and velocity also.
At the exit the bullet is going just below the sound velocity.
Therefore we have : 125 grains, 1000 fps.

  1. If we compare the two momentum we see : 33 grains difference, same velocity
    it makes a 26 % increase in momentum for the first one !

  2. The ported barrel silenced guns have other problems :

  3. if the gun was designed to reduce the speed with one kind of ammo, and if you use another kind of ctges having a lower velocity (in a standard barrel), of course you will have a lower velocity at the exit.

And you can be at 800 fps for example (the decreasing in velocity is not proportionnal to the velocity of the ctges tested in a standard barrel)
The momentum is decreasing a lot !

  1. the accuracy is not as good (because of the holes)
  2. to clean the integral silencer is a lot more difficult

The ported barrel silencers are old designs and show lack of efficiency on a live target.

They are very silent because the velocity of the bullet is often very very low.

(For US readers, all the suppressed weapons of Jonathan Ciener were like that.He stopped to manufacture silencers because of liability, paperwork and so on, but also because there was no way to compete against the new silencers (which are chemical).

  1. Even 147 grains going to about 1000 fps doesn’t give you a good margin when you need to be sure to kill.
    If you need silence and if the guy is not killed at once and has time to roar, it is not good !

The US seals at the beginning were using 175 grains bullet in 9 para.
The weapon was a S&W Auto pistol Mle 59 (or something like that)

But the design of the S&W was not strong enough to support such loadings and they stopped because of too many accidents.
After they used 147 grains bullets.

  1. there is something people don’t understand.
    When you have a silent gun and if it is well designed, you have the same velocity (about 1000 fps) and this for any caliber.

The only parameters you can play with are :
bullet weight (heavier it is better it is for momenteum)
bullet diameter and bullet shape (this is for terminal ballistics)

Therefore , for example, a 30 Nato or a 300 Weatherby magnum will be exactly the same if you can put the same bullet.


JP is correct about the ported barrel SMGs with the wrong ammo. In the extreme case you can get a bullet stop in the barrel-in which case you have zero effect on the target. I once saw a Sterling (A13???) ported barrel that had been fired with WWII Mk1Z ammo. The first bullet stopped near the muzzle and subsequent bullets filled up the barrel as it was fired, with lead extruded out of the barrel ports. Eventually it jammed because the barrel was totally filled and the next round would not chamber. The guy firing it returned it to the owner who hung the barrel on his wall. I think most of the Brits on the Forum will know the owner of the gun.