What brand of 20 gauge hulls would you recommend to buy for reloading and what would be a good price?
AA or Gun Club. Whatever you want to pay - some folks are paying more than 5 cents each plus shipping if not local. Check where there is more skeet & sporting than trap, you’ll probably find barrels full for free.
Gun clubs load better than AA's or STS for me as the new AA's seem to require more wad pressure with clay buster wads, that said you will get more life from a AA/STS IMO YMMV
I am using Federal hulls with Longshot powder and have been happy with it. I get mine free at the gun club as the high school shoots them. Ask around you should be able to get free hulls. They all work it is just a matter of what wad to use.
I would add the only issue that I know of with Gun Club hulls are that they are steel, not brass, based. Some say the steel hulls don't resize well, at least not like the brass based hulls on the AA or STS. And, several of my friends have said they have been told by folks at Krieghoff not to shoot steel based hulls in their guns. I can't verify that statement first hand nor state what the issue may be in using steel based hulls. Hard on extractor/ejectors perhaps or. . . . . . . . ?
Personally, I have always preferred Remington for 12 and 20 and Win for 28 )I do not shoot a 410, but those who do that I know also prefer the Win for 410
Here's another vote for Gun Club hulls. I get at least 10 reloads with them in 12 and 20 gauge. Regarding not using steel base hulls in Krieghoff shotguns, I have fired tens of thousands of steel base hulls in my Krieghoff and Berettas. There is no problem with my guns' chambers or breech faces.
not all gun clubs are white steel. some are brass finish coated. most are the 6 pointers. work great.