I know a guy who brings all gauges on his opening weekend hunt, from a 410 to a 10 gauge...he shoots a bird with each...so, sure, a 28 can kill a rooster...having said that, I have lost LOTS of birds over the 27 years I have been hunting pheasants intensely and most of those years have been with a 12 gauge throwing 1.25 oz of 5's at 1300+ fps...and a good % that come back to me are alive...I don't want to make it harder than it already is. But I love my 28's! shot a lot of sharp tails this year with them...and a few huns...and a ruffed grouse yesterday...magic little wands!