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.

RE: Quietest deer gun/caliber
 

The problem you may run into is barrel length. A 44mag has a low volume of powder, but is generally offered in carbine lever actions. The longer the barrel the less noise, So you need a minimum of 24" in a lower caliber. The 6.8 spc comes to mind. if you don't reload. If you do there are countless cartridges that will fit the bill.
Blessings

RE: Quietest deer gun/caliber
 

For such close range, the 223 aint bad