Precious and grace,
I looked in my Lee modern reloading manual the 22 hornet[19 cahoun's parent case] burns 14 gr of accurate 1680 powder and the 221 fireball burns 20.5 of 1680 both using 40 grain bullets.That might give you a ballpark idea of the sound levels.The 17 hmr burns 4.5 according to varmint al's site.
I have a cz 527 221 fireball and it is a great little rifle,although i'm not in any way trying to pull you away from the 19 calhoun.I read some of Calhouns site and am impressed again,[it's on my favorites list] all the 20 caliber stuff has shadowed the 19 cal in the last couple of years.I read the site 3-4 years ago and thought about making my cz a 19 fireball,it shoots so great it would be all but impossible for me to rebarrel my 221 fb..
I started reloading about 1 1/2 yrs. ago and would highly recommend it to everyone.Just go and get a basic reloading kit with manual $80 and start browsing through it and looking at the press, scale,priming tools,get a caliper also."You don't have to throw yourself into it 100% the day you get it". In no time at all you'll see how easy and fun it is to handload ammo,I just loaded 300 rounds in an evening -while listening to the radio.
CZ rifle >Handloading >19 cal.What more could a guy want?Get your keys-shoes --go get it..ME
P.S. Lapua is going to make brass for the 20 cal. vartarg "basically 221 fireball",great brass compared to remington brass,it will neck down to 19 easily enough.