Polish 5.56 M855 for SDI 2016?

I came across the retail website of DS Arms in Lake Barrington, Illinois (northwest greater Chicago) and they are offering some M855 in odd packaging which says “Made in Poland” as well as “for SDI Inc., Illinois, USA”. I’m not certain if this “SDI” is Security Devices International, or the gunsmithing school “Sonoran Desert Institute” or what - neither of which are in Illinois. Googling didn’t help much. DS Arms has offered these boxes for around a year at this point anyway, and the headstamps are 2016 dates. Mesko I presume?



Matt, thanks for sharing this! Great info!

Matt - everything about the head of that cartridge screams

John Moss

SDI = Security Devices International ???

It would make sense if it were Security Devices International, although they are near Toronto. I just found a story at the below link about SDI enterring into an agreement with a CDS of Chicago on some inventory purchasing and resale agreement of some sort though


Is this ammo available anywhere by the box? It is interesting but a case is a LOT more than I’m interested in.



Yes, link below.



John, the “21” in the lot number does not even scream! :-)


Many thanks. I just didn’t look properly at the website. Thanks for correcting my mistake.

Good news is they also offer Polish made ammo in 7.62 NATO. Box image below.

Note that this lot number also includes “21” Will post the hst when they arrive.



Lew, well done finding the 7.62!
I wonder what the “IPL” in the lot number means.
As Romania is using “R SD” after some sort of measure predicted by the law I would not be surprised if this is something along the line.
A long shot maybe but could it be some new EU regulation (or soon coming) where lot numbers have to ID the country???

SDI is the company that handled the importation for DS Arms in late 2016, but it not longer exists. The initials stand for Strategic Defense Imports, Inc.



Cases was fired during testing / receipt of the batch of this ammo in Mesko:
SDI and “DA”, DA probably for Dillon Aero M134 Minigun.

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The DA is a Minigun loading with a 165 gr bullet made for Works 11 (Dillon Aero’s representative). It’s packed with M13 links in US made 1500 rd. boxes.

The SDI Contract cartridges are loaded with a 146 gr bullet.