FN Grenade Launching Cartridges


While looking for a sealed 20 round box of USGI grenade launching cartridges i found 2 of the boxes below for sale and purchased them. One box is still factory sealed and the other was scotch taped shut many years ago so i opened that one to examine one cartridge. I’ve been told “they are made in Belgium by FN, for use (and probably sale) with their ENERGA type rifle grenades. These were tested as T-42 and adopted as the M31 by the U.S. in the early 1950s, but as far as I know we used our own cartridges with them. There may have been a standard NATO agreement on this type cartridge by then, but I cannot swear to that. Chris Punnett’s superb book ‘.30-06’ does not mention these, and only notes that most of the FN crimped type blanks were believed to be ‘noise’ blanks, so I suspect this is a pretty rare box.”

I’d appreciate any additional information anyone can share with me on the origins of the box. I only need 1 box for my collection so if anyone has a sealed USGI 20 rd box, 9 round box. and/or a mini spam can of USGI Grenade Launching cartridges, we can likely arrange a trade.


As you say, these are grenade discharging blanks for the Energa grenades.

I don’t know how rare the box is in the U.S., but here in the UK it is not rare. The British military adopted the Energa grenade about 1950 together with the FN blank as the “Ctge, S.A.Rifle Grenade .303 inch H Mark 7z”. The earliest production (1950) had plain brass cases like yours, but by 1951 they were marked in the standard British way for discharger cartridges by having the lower half of the case blackened.

Pictures attached.



Here another one for a tear gas grenade. Were these for Belgian forces or police?


The U.S. manufactured Grenade Rifle, Practice (Inert) M31 used the standard Cartridge Rifle Grenade, Cal 30 M3; two of which came in the container with the grenade.

Unknown cartridge

Phil, do you have an image of these US propelling cartridges?


EOD – Here is a M3 that has the same headstamp as those in the 2-round packet attached to the grenade (I think).


Thanks, now I am a bit confused. I always thougt that there should be a 7.62x51 cartridge. Was there such one?


The Belgian Energa Grenade was first developed for the SAFN 49, hence the use of .30/06 Launcher Cartridges; The British adopted it and its 22mm Launcher Tube for the Rifle No.4, hence the .303 Cartridge;
The Belgian Police also had .303 cal. Rifles (Both No.4 and No.1, obviously the Laucher was fitted to No.4 Rifles), and the FN-FAL, itself first in general issue in 1953-54, then had the Energa attachment and a 7,62x51 Cartridge supplied.

The 7,62 Launch Cartridge was usually supplied (one of) in a Plastic Plug fitted in the tail-fin tube assembly ( From an Italian version of the Energa grenade).

I fired quite a few Black (inert practice) Energa grenades whilst in Infantry in the late 1960s (from L1A1 Rifle.).

AV Ballistics.


EOD – Yes, there is a US 7.62x51mm Grenade Cartridge. It is the 7.62x51mm Rifle Grenade M64 (from the .30 Cal. Rifle Grenade. Light Rifle T116 series). The earlier Cartridge Rifle Grenade, Cal 30 M3 was used from about 1941 until it was replaced by the 7.62x51mm version.


Phil, thank you for enlightening me!


Doc why do you think the Energa was Belgian? The Energa grenade was developed and patented by Edgar William Brandt (the Frenchman that also became famous for his Mortars) in Liechtenstein and later in Switzerland. Belgium (namely MECAR S.A.) was just the largest producer of these grenades since Energa (“Anstalt für die Entwicklung von Erfindungen und Gewerblichen Anwendungen ENERGA in Vaduz / Liechtenstein”) was just a design bureau without production capabilities which was giving licences to customers.



Whilst Brandt ( of Hotchkiss-Thompson-Brandt) may have had his design etc bureau in Liechtenstein, the Development and Production of the Energa grenade was all done by MECAR SA; The Belgian Army was the first to adopt the grenade for the SAFN 49, and FN continued the Development of the Launching Platform for the FN-FAL, whilst Britain
adapted the Belgian Tube for the Rifle No4.

I don’t know if FN also adapted it for the M1950 .30/06 Mauser, but probably did, given the large numbers of these rifles produced at the time.

Interesting sideline of ammo development.

Doc AV


DocAV, I don’t believe your statement is correct. There is no patent evidence showing that the development of early ENERGA grenades was done by MECAR SA. All rifle grenade patents filled by Edgar William Brandt of Geneve, Switzerland were assigned to Anstalt für die Entwicklung von Erfindungen und Gewerblichen Anwendungen (ENERGA) of Vaduz, Liechtenstein.

It is also incorrect that the Belgian Army was the first to adopt this grenade for the SAFN 49, because the Swiss Army adopted this type of rifle grenade for their K31 repeating rifles already in 1948. Some trials of this combination (K31 & Energa M. 48) were tested by the Argentine Army. Cartridges used were those designated Treibpatrone 44/48 which are pretty well known by collectors.