RE: Quietest deer gun/caliber
My dad's 7mm-08 isn't bad at all compared to my 30-06. I personally think 7mm-08 is a good round.
But maybe a .243 wouldn't be a bad choice.
I think someone said this already... But if you have a mussel-break, take it off. If you were in Iraq, I can understand the use of a muzzle break. But we are talking about deer hunting.