But, 1 ounce ot 1 1/8 ounce of 5s or 6s thru an improved cylinder or modified choke will work fine if the scattergun is pointed correctly.
3" for most pheasants in Pa. is wasted oomph and recoil.
The brass height itself means nothing....mostly marketing and shelf appeal.
Brass is not actually needed other than for extraction issues at times.
In the Past, all plastic shells such as the Wanda, et al illustrated the concept.
Look to shot weight, pellet size and velocity if one is worried about fit of a shell to a bird....actually, not much won't work when pointed correctly and triggered appropriately.
Consider patterning any shell choice if a question remains but, essentially, keep wood to wood and good luck.
A little load education for ya, high and low brass
actually mean little. Mass produced shells usually use High brass shells when loading high FPS mixes, however what you are looking for is repetative patterning, shot size and FPS when judging shells for different bird hunting. If you purchase stock shells, IMO one of the best for Pheasant hunting is the Fiocchi
Golden Pheasant #5 or #6. The 16' gauge shells are fantastic for Pheasant hunting Copper & Nickel plated, 2 3/4 lgth, 1 1/8 oz, @ 1310 FPS that put down pheasants cleanly. If you have a 16 gauge double gun these are about the best Pheasant hunting shells around, IMO the only way to beat them is to make your own. I use these shell in the 2nd BBl and the Fiocchi High Velocity 71/2 @ 1300 FPS in my 1st BBl, a deadly combination for Pheasant hunting.
These shells are tested and shoot repetatively in the same manner holding very good patterns out of most shotguns, another important factor.