H4227 was made by AUstralian Defence Industries (ADI) who also made an identical burning powder but with a coating to reduce temperature for loading .223 for the Australian military marketed at ADI/Mulwex AR2205.

The two powders were interchangeable for reloading data but the coating meant that AR2205 metered differently from powder measures. A little more space was taken up for an H4227 equivalent weight.

Back in the ‘90’s I tried both powders in .38 Special and 44/40. In both cases I preferred the Hodgson powder over the Mulwex powder.

At some time both Mulwex and Hodgson were owned by the same parent company and a question was asked at board level “Why are we making two basically identical powders”?

As a result H4227 was discontinued while AR2208 remained for the military contracts. I cannot find anything definitive to confirm this but I believe that what is now known as H4227 in the US is actually AR2205. H4227 is no longer available down under.

For a few years I replaced H4227 with AR2205 in my reloading, but it was never as accurate for me in my guns, so I switched to Tightgroup.

I have no experience with IMR powders but if they are now referred to as being “the same powders” by the manufacturer then again, I suspect it is AR2205.

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View from down under