Hahaha, you described that so well that I can instantly picture that scene. I bet it was like someone letting off a red dirt bomb inside the cab hahaha. That reminds me of when I shot my friends M107A1. We were at a nice, private gun range shooting at a table that was under a roof to keep the sun and rain off of the shooter. I only shot it once and the concussion from it instantly evacuated my sinuses. I will never shoot one of those ever again under a covered anything. My sinuses were stopped up before shooting it, not so much afterwards. I don't know if it would have been that big of a difference on me if I would have had clear sinuses to begin with but I'm not willing to try that again either way haha