It could be that you are shooting the weak little Federal Hydra-Shok load from your .327. That would be an answer right there. Pick up some Gold Dots or make some proper ammo for it yourself.
I don't know about that.
I agree with him, that the noise level and muzzle blast are about the same as a comparably hot .357 Mag load. And I've been experiencing .357 Mag noise/blast all my life - in anything from a 2" barrel, to a 6" barrel.
I had some of the factory .327 Federal Hydra-Shoks, Gold Dots, and American Eagle SPs on hand for side-by-side testing. It was .327 SP101 vs .327 Blackhawk vs .357 GP100 (4"). Hot loads in the GP100 were as punishing, or more
punishing than the SP101's noise level and muzzle blast. I still don't think they were worse than a .357 Mag, but the loudest/blastiest (
) factory ammo was the American Eagle. (I didn't bring up the Blackhawk, because noise levels and muzzle blast are much less apparent than with the SP101.)
That's just my opinion, though.
Maybe proper test instruments would show otherwise. Who knows?...