Well, yeah, the environment defiantly has a factor on your ability to do quick motions, I won't deny that. When I timed myself I was on a quiet shooting range in Boston (Well, Sudbury) in the fall. While someone is yelling at me and I see other people firing, there's going to be some variables thrown in there.
I also did cheat a bit, I kept my rod on my belt and pre-tore the cartridge. I'd say in battle I'd have a 20 second speed.