I have several Sav. Dry system pipes, they have a wide flat bit and much larger stem end. Use a the small diameter cleaner or bristle type. I solved the shank to bowl separation problem by coating stem joint with wax. Also the costly filters can be had in long sections from hobby shops.
Old trick is to bend the pipe cleaner a little, and give little twist while pushing it in the draught. With luck, it will actually get to the stummel. But that's an army mount. Taking stem off to clean is the best way.