Not really. That is WHAT they used and WHERE they found it - not the same as answering WHY they used it.
We don't know for certain WHY they used it, but it may be reasonably deduced from the (intentional) effect of the article.
The use of the image in this article, with its MSSA caption, has the effect of suggesting a guy used a .308 MSSA against his neighbours.
The motivation behind this could be just because the journalist's integrity has been prostituted to sensationalism... or because of some Australian type gun control agenda which no inconvenient fact must stand in the way of... or both.
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