A thought, we've never had success for chum near their spawning rivers.
It may be that you have to intercept them a little farther away when they are still feeding?

Smiley.

I know it is a total different thing fishing chums away from the rivers influence, but when I used to fish them in Queen Charlotte Sound, speed was important. Used to poke along with the flashers just barely rolling. Stacks of gear.

If I was to try here I would begin with a sockeye rig- dummy flashers and slow. Anybody tried that?

I have caught them occasionally off the Fraser River mouth on hoochies. You'd expect them on mini plankton hochies, but I'd sometimes catch them on Octupus size. Glow in the dark, or army truck hoochies, slow troll with short 28-32 inch leader.

you can get them on herring ,tighten up on your leader length,troll slow and set your distance from flasher to release pin closer.they like it slow it seems but you stilll get good action by tightening up.Ss......

just a reminder to check your downrigger line often especiallyat the ball and release points,yesterday i found a nick almost halfway through at the crimp point,had to change it out there, i check every time i go out fot an ounce of prevention is worth a pound of cure,have lost expensive stuff because of not doing thorough check every day,Ss out...........