5.56x45mm Matte Nickeled Cartridge Cases From Lake City Apparently Part of a Corrosion Test

Forum member FrankN last year obtained a small group of 5.56x45mm nickeled cases from IDAHO ORDNANCE FACTORY located in Dalton Gardens, Idaho. IOF purchases bulk 5.56x45mm cases from Lake City Army Ammunition Plant (LCAAP) and in one of the shipments IOF received from LCAAP was a batch of nickeled cases. The word was that these cases were left over from a corrosion test, possibly for the Navy.

Below are examples of the primed nickeled cases and the headstamp found on all the cases that Frank received from IOF:

Nickeled 5.56 x 45mm Cases From Lake City, b

So can anyone provide additional information about these plated cases from LCAAP?

Were they for a corrosion test or something else?

Any help would be most appreciated!



Brian, are you sure this is a nickel surface and not something else, dull as it looks?


Good question, no we are not certain of the plating material.

The only thing Frank and I know is that IOF described the cases as being nickel plated.

We are open to any suggestions or information including what the plating material might be.



I forgot to mention in my opening post that these case are also platted on the inside of the case just like the outside of the case. Since the surface of the inside of the case is unscratched the plating is white silver in appearance when exposed to a bright light.


I think the original source for these LC 17 cases was Bonaduce, Inc. (“Poly Gun Bags and Supplies”), where they were described as new unprimed high pressure test cases.



IOF loaded these cases with 55 gr. FMJ bullets:

They also used these cases for cartridges loaded for Black Rifle Cartel:




1 Like


Thank for an answer that seems so obvious and simple…
…after one is presented with the answer.



Brian, since the inside of the case is plated that gives away the type of plating: Electroless Nickel (usually a Nickel-phosphorus alloy). Electroless nickel plating is also known as auto-catalytic because the nickel plates out from a chemical bath spontaneously without an electric current. Electroplated coatings typically will not “throw” (i.e., coat) to the inside of something like a cartridge (deep hole) unless an electrode is inserted inside, but the electroless process will plate inside as long as there is sufficient agitation to keep fresh plating solution inside.