If your good, 30 pellets wont matter..... speed kills
I think 30 more pellets do matter, but 1300 FPS is just too slow. I have gone back and forth with kent #4, 1 1/4 load @ 1425 FPS vs 1 1/8 load @1560 FPS, and I also patterned both. When I patterned them, I was sold on the bigger load, more pellets in the pattern with the bigger load at 30 yards, and both went right through my pattern board. So I figured if both went right through the pattern board, they both would go right through a duck, but this is not the case.
Everyone says speed kills, here are more specifics. Ideally, you want the pellet to go right through the duck, in the breast, thru the vitals, and out the back of the duck. Next best is through the breast and through the breast bone. Even at 1560 FPS, you are not going to always get this. At 1425 FPS, you will be digging more pellets out of the breast meat, more blood clots, etc...At 1300 FPS, not sure I have ever shot a shell that slow, and on top of that #5. Good luck with it.