30x55SR and 30x55 rounds for XM19 grenade launcher


Is there any info (docs / images) available on US made 30x55SR (later adapted to 30x55)?
The weapon for these cartridges seems to be the XM19 rifle / grenade launcher.

30x55mm grenade, anyone know what this is?

Concepts of Single Shot Grenade Launchers Attached to an Infantry Rifle. Final Report. Nov 1970-Feb 1971,
ARMY WEAPONS COMMAND ROCK ISLAND IL . http://www.dtic.mil/docs/citations/AD0887066

30 X 55 SR Honeywell http://www.bocn.co.uk/vbforum/threads/44692-30-X-55-SR-Honeywell


Brian, thanks a lot! This is great info.

Just if there would be more on the ammuniton.



I agree, hopefully others on the Forum will have more information.




Brian, thanks again! I remember that image.


Thanks Brian! I have one of those rounds, and it’s good to learn more about them.


Some small bits of background information:

From: http://looserounds.com/556timeline/556dw-1972/

THE 5.56 X 45MM “TIMELINE” – 1972 A Chronology of Development by Daniel E. Watters

“The US Army awards a contract with the Honeywell Corporation’s Ordnance Division (now part of Alliant Techsystems) for the development of a 30mm grenade cartridge to replace the existing 40x46mm. (The actual design is credited to Picatinny.)”

http://gunhub.com/automatics/40870-mystery-grenade-launcher.html Daniel Watters

“According to Jane’s Infantry Weapons: 1997-98, the EX-41 was developed by US Naval Ordnance Station - Louisville, KY. It was created for the USMC, which was studying possible replacements for the M203. It was also evaluated by ARDEC’s Bursting Munitions Technology Assessment program. The early live-firing prototype was a four-shot, pump action launcher weighing 9.98kg. The launcher was 914mm long and 279mm tall.”

“The cartridge was not a standard 40x53mm HV cartridge, but rather a hybrid, using standard projectiles for the 40x53mm in a cut down case. The cartridge possessed a muzzle velocity of 152m/s with a max range around 1,500m. At the time, they hoped to improve this to 3,000m and reduce the launcher weight to 6.8 to 8.16kg. However, it was expected one or both of these goals would have to be sacrificed due to the anticipated recoil forces.”

“Another interesting item studied by ARDEC around the same time was Alliant Techsystems (ATK) and Knox Engineering’s Individual Grenade Launcher System (IGLS). It was a ten shot, semi-auto 30mm grenade launcher. It was 813mm long, weighed 5.9kg loaded, and was credited with a range in excess of 500m. The 30mm grenade appears to be related to the same design developed back in the 1970s by Honeywell’s ordnance division (now ATK) as a possible 40x46mm LV grenade replacement for the Army. The 30mm grenade was reported to have the same terminal performance as the 40x46mm, but with lighter weight and slightly higher velocity. Back in the '70s, the idea was to design a light, multishot grenade launcher using the 30mm grenade for the Future Rifle System (FRS). Prototypes were even tested for the M16A1. However, this design didn’t go anywhere at the time.”


Here’s an example of the 30mmx55 case from my collection. Going by the bare aluminium around the rim edge it appears to have originally been the semi-rimmed version, then machined down to rimless. The markings on the side are ‘28010147-001’ and ‘30MM APERS VM 1-2’. The pictures show the ‘hi-lo’ primary chamber partially screwed in & removed.


Muskey, thanks for showing the unscrewed primer/propellant container!


If I’m not mistaken, George Reynolds is the connecting link between the FRS launchers and the later Knox Engineering IGLS design. Reynolds has also done some sub-caliber trainer design work for the Mk 19 GMG on behalf of the modern Armalite.


Daniel, is there more info available on the sub-caliber trainer of the MK19?
Haven’t heard of that before.


I call this a 30x56SR AAI experimental practice APERS grenade. I was told only 300 were made from WECOM cases. Rim is 33.6mm diameter. Case is 56mm.
Is this what you are referring to as a 30x55SR or a different grenade?
What is the correct ID for my grenade? Info is hard to find.



The cartridge case & projectile you show are mentioned (with photo) here but without any additional information, see discussion and pictures here (you must login to BOCN as a member in order to see the pictures):




Ron, the case I have examined was 55.2 mm long.
Your’s here has a somewhat different base construction than the known ones (also different finish).
Also your primer appears to be an electrical one - can you confirm this?
As your case is the semi-rimmed variant one could guess that the case length is not as crucial as with cases where the case is chambering with it’s case mouth. Also during development of a weapon/cartridge minor changes are not too unusual.


EOD and bdgreen.
I am trying to join BOCN. I found my De Hek book page D.197 has drawings and realise you refer to the Honeywell while mine is the AAI. Different grenades.
The primer seems normal, copper with a dint mark. No insulator.
I include a view of the unscrewed nose cap so just enjoy the photos. Cheers.



Here is the picture of the APERS round posted by SG500 from the BOCN discussion mentioned above:


Also in the same BOCN discussion is a photo posted by Hazord in which there is a cartridge case the same as what you picture above.



Ron, very interesting!
What was the difference between the Honeywell and the AAI? Was it different weapons and different projects?


EOD. I know only what is printed here from De Hek book “Military Cartridges” part 4
page D.197. I have lots to learn about experimentals. I do like them.
There is 4 volumes in this book set and very good references.
I hope this page shows the differences in dimensions.


I have these books somewhere. But not on hand right now, thanks for the reminder!

It appears that the Honeywell rounds were for the pump-action type launchers (as per the flat proj. noises) and the AAI design has a different OAL and seems not to have been for a pump-action type launcher (unless the primer is seated somewhat deeper).