Huge Fly Guy
Is the thought that spawnfly jig shanks strong enough for tuners?
I have no idea. I'm using these other shanks (no idea on brand) that overlap on both sides, throw on multiple thread layers, then glue it down before I even start constructing the fly. I've used them on occasion for tigers and haven't ever had one even start to come loose after multiple fish (not the best comparison fish-wise, but at least they pull hard and are heavy)