I recall some five or so years ago the general word from choke mfgrs was that size 5 shot patterned best in 20 gauge guns. Also the most popular choke size seemed to be 575. Then it was 555 and Kick's 560, TG's 565 etc.
I know that the first of the H-13 #6 shells loved 555 and then along came the fix it till its broke shell fiasco(H-13). Getting good patterns at 30 yards is no problem whether it be lead or HTL using#5,#6,or#7.
It must be partly me but I seem to always get better patterns using #6 shot over #5s and no question on #7 patterns. For those who are getting anywhere near 100+ pellets lead or HTL at 40 yards using #5 shot or larger what choke and shell are you using? This is for 20 gauge guns .
As I said in the PM I love
HV5's from winchester
Gun is a mossy 500 sumtoy 5 ring super 62 (.562 choke)
cleaned barrel with steel wool
.565 Truglo GSX
Federal FC 3" 1-5/15oz #5's
(http://i162.photobucket.com/albums/t244/sr5865/S4021451.jpg)