I have this one in my collection but no notes

The dimensions are 5.56X40. Where did this one fit in?


Daan, this is one of Olin’s versions of the XM144 cartridge and is designated XM144WE1.

Thanks Fede,
Comparing them, am I correct as follows:









There are others. The WE4 is one that immediately comes to mind. Also, the 5.6x52 SBR (saboted 4.32mm bullet). Do a search. I remember that the flechette cartridges have been discussed several times before.


Hi Daan,

I think the round you have labelled as XM144W is in fact the XM144WE4. Another round in the series is the XM144E2 and E3. Both of these rounds use a modified E4 case with shortened neck (c/l = 43mm). The difference between the E2 and E3 is the length of the flechette (42mm vs. 38mm). The flechette style is the same as these E1’s. The E2, E3 and E4 are all headstamped ‘W C C 6 2’ and use the small primer.

Fede – thanks. You beat me to it. Here are some variations that used a compressed material to act as the sabot.


Paul, that’s a wonderful group of variations! As usual, thank you very much for sharing pictures of your great collection with us.

Another interesting feature of these cartridges is the use of Olin’s Bloem type primer, instead of FA’s miniature Boxer type primer.

Paul, thanks for posting pictures of these rounds. I have never seen one of these compressed material sabot rounds before. Now I have even more stuff to hunt for!


I should have been more clear (clearer?) about that 5.56x52mm cartridge. It is not a flechette but a SBR (Serial Bullet Rifle) cartridge. A last gasp effort to salvage something for all of the taxpayer dollars spent on the SPIW project. It wasn’t successful either.


I have to admit that I do not know what you mean by Bloem primer (Braun & Bloem ?). Could you elaborate a bit?

Jochem, yes, it was based on the design used by Braun & Bloem. We discussed this subject here: iaaforum.org/forum3/viewtopi … =8&t=12497

The checklist should be updated to include these series of cartridges.

Do I understand correctly that the SPIW-book did not describe all known flechette cartridges of this project?

Not even close. SPIW was just the beginning. Search for photos of Pepper’s flechette displays. Prepare to be amazed.


Ray, thanks! Is anybody going to write a book on them maybe? It seems to be a quite popular subject with many unknowns.

thanks for the hint.
Pronounciation “Bloom” is very probably correct, by the way. Gustav Bloem was born 1821 in Wesel (died 1905 in Bald Wildungen). In this part of Germany “Bloem” would very probably be spoken the Dutch way, which sounds like bloom. Bloem is Dutch for flower. So in this case Bloem is not an alternative writing of Blöm but an original name. (I was also born in this area of Germany.)