Yrs back I used to go regularly to the Knob Creek MG shoot in Kentucky, right next to Fort Knox!
They shoot a lot of suppressed stuff. They have a separate range in the back so you can really
enjoy suppressors with ear plugs out. My pal had a pre-'86 2-stamp MP5SD we used to run on the
"jungle walk" course in the back - nice!
Key issue: It's the
hi volume hi speed gas at the muzzle that make the suppressor less
effective in .223, etc. Flight noise from a supersonic round doesn't carry that far, more like
a fast whizzing sound, not a bang. Any bang you hear is the unsuppressed portion of the blast,
not the sound of the actual bullet.
The heavy .300 blackout round delivers decent energy with way less chamber pressure acting on a
larger sectional area of the bullet then the much smaller .223!
Locally up here a few weeks back, cops where at the range using small muzzle cans on ARs, reduced
the .223 blast to a light .45 report, looks like their guns were set up for CQB use. Compact cans
(suppressors) only do so much, I'd rather have the MP5SD, way quieter, the action sound you hear
thru your cheek bone (cheek weld to the stock) is a bolt 'clunk' rather then a "skretchy screen
door" sound of an AR bolt carrier and buffer spring cycling! LOL (But I'll still keep the AR!)