I'm writing a research paper regarding a battle where I intend to write something like this: Apparently not satisfied, the General "dismounted from his horse and gave some directions about sighting the gun," the witness recalled. Across the way, and at that very moment, a Union artillerist was doing the same thing and after the Yankee's gun-sight was set, and after the cannon's lanyard pulled, the resulting explosion sent a spiraling, percussion-fused projectile near the speed of sound towards the Confederate gun line."
I would like to know whether my referencing "near the speed of sound" is a reasonable description if the gun I'm describing is a 3" ordnance rifle firing at a target 350-450 yards away?
Thanks.