At Desert Brutality and 2GAC matches they do it the mil way (although people are allowed to use flags if they prefer). Having at least been a poxy cadet and UOTC peon I had at least done it that way 2+ decades ago and it was easy to get back into that mindset, once the initial "huh" had passed. It's a discussion point in an upcoming vid I filmed with Karl, cos it's something that surprises some people.
The historic crowd cause even more trouble:
"Uh, my rifle magazine is not detachable"
"uh, my rifle doesn't actually have a safety catch"
"Uh, I probably won't be able to unload without firing off the rifle. You see the cases are very tight, and..."
"Uh, I need my tools and a workbench to get the bolt out"