Can a nonported choke cause this?

[RiverRoost]

Got a friend who just picked up a sx3 longbeard 20 gauge and he tried the factory "longbeard" choke that came with the gun with Federal 8&10 blend. The choke is not ported and the pattern looked horrible for 40 yards. I picked him up a Carlson longbeard xr.568 choke that's ported we are going to try with the federal blends before moving to straight 9's. Will the nonported choke that came with the gun cause the pattern to blow out or not have a defined core like he got when he shot? I'm thinking the ported Carlson is going to do a much better job, I hope atleast. If it doesn't then we are going to try the straight 9's and see if that changes anything.

[Reloader]

Porting doesn't matter as much as design. There are plenty of nonported chokes that pattern very well. Did he shoot a large sheet of paper and catch the whole pattern?

[RiverRoost]

Yes he did. There isn't a defined core to look at anyway, just a big even flat pattern. I think the factory choke that came with it is arounda .570 and I have a .568 to try. Not much of a difference but I'm thinking between design being different and it being ported it could be a big difference in the next pattern. His gun is new and aside from the bird shot to dial in the red dot I don't think he cleaned it so I told him to clean the barrel good too just to be sure and get any oil etc out of there.

[tnanh]

I dont shoot tss but my experience is when a pattern blows with no true core go more open, not tighter. A Carlson 575 has been the best all around 20 gauge choke I have shot in various guns and I have one in three different 20 gauges. I shoot hevi 13 7s in mine and an acceptable hunting pattern. I also have a Sum Toy in my last 20 gauge I like a lot.