That's not true. The standard US Army shotgun is the Mossberg 590. You can buy one at any gun story. The standard US Army sidearm is a Sig-Saur 9mm semi-auto pistol which, again, you can buy at any gun store. For years one of the US Army's standard sniper rifles was a variation of the Remington 700. This rifle has been one of the most popular civilian deer hunting rifles for decades.
https://www.youtube.com/watch?v=1VADFpAfDLY