ORIGINAL: backcountryjlaf
Here is my personal opinion. There is no correct shell. Personally i won't shoot anything smaller than a number 6 on pheasants, i usually load 1/4 oz 2 3/4 inch #6 in a modified 12 guage for my bottom barrell, and then a #5 1/4 oz in 2 3/4 inch in a full choke for my top barrel. I worked out my loads as fast as i could get them, and i have downed birds with number 6 shot at 40 yards (havn't found a number 6 load that will do this consistenly yet, but i've done it) I find that shots inside of 30 yards in my gun my number 6 does the job every timed, and if i want to stretch it out a bit the heavier pellets give me a bit of extra range.
I think that you should look at what most of your shots are, and what kind of shooter you are. If you kill most of your birds inside of 20 yards, a number 6 will do just fine, and you might want a heavier load with a wider choke, if you are going to do a lot of long range killing you are going to want big velocity with enough weight to do some damage, and a tight choke that is going to give you some sort of pattern at that range.
To be very honest i think to much focus is put on shells, if you buy decent shells and make good shots you are going to kill birds. Very seldom does the shell make the difference, but it does on occasion, so why not be prepared. There are a few good sites that reveiw steel loads and rate them but i havn't found any for lead yet.
there was expert that researched best shell /load to use and why..he said we are wrong for using high brass loads like 1 and 1/ 8 and 1 and 1/4 shot..in the 12 ga..
not to go into all details..he said heavy dram loads like 3 and 1/4 powder push pellets and deform them..he said you will get a2 ft sideways pattern NOT a pancake pattern at 30 yds and beyond..this causes a lot of pellets to not get to bird etc..
to sum it up, he rec using only 2 and 3/4 inchLOW BRASS ,3 drams and1 oz shot..1 oz shot will STAY TOGETHER all way to target..he has point,skeet/clay shooters also told me that is reason that they use those type ofloads for their shooting..its not cost of the HEAVY GAME LOADS, IF THEY WERE BETTER they would use them on skeet etc, its that the pellets stay together..
also expert said, we are foolish to buy the heavy game loads, they are a marketing ploy..
i was set back on this too but it made sense after you think it over ..he should know, he testedthis out..
after that i went back to just 2 and 3/4 inch,1 oz shot ,3 drams and low brass on grouse and i shot pheasants with it too..i knocked pheasant out of air dead at 40 yards with that load..
no more high brass heavy field loads ever again..if someone is interested in this experts article i will try to find it on internet..