Agreed those seal are a major design flaw. On my 50th gf brew today and yet another series of attempts to get both seals fitted and in place. I think the seals stretch with age and also the grain tube may go out of true, slightly oval rather than round. I normally ensure the grain tube has good dusting which does help and slide down at an angle before rotating into horizontal but usually takes several attempts. I had wondered whether they were actually required and from comments above seems not so may well go that way. I do have to ask why is the bottom one not integral to the tube? ie a bucket with a perforated bottom this would be much better, no dicking about with seals and no risk of the bottom falling out.