What do you mean by "they all seem to have four"? Do you have multiple 1st stages with one washer missing?!? Any chance one has just been inverted and is nesting next to another one?
There have been a lot of variations of Sherwood Magnum. I doubt that some used 4 washers and some used 5, but perhaps you should supply a couple of good photos so I can look up the exact item and verify the count with you. I checked the 5000/7000 series, and yes that uses 5.
Also, I am pretty sure they are still available from Sherwood.
I have four Sherwood SRB3300 first stages and I think they all have four of the washers. I don't see how i could have mis-counted but I suppose it's possible. My girlfriend will be happy to tell you that my memory is flawless--I never fail to remember anything incorrectly
I'll look and see if any are nestled, like you said. I make a sketch of how they are stacked whenever I dis-assemble one but I'm thinking they were all stacked the same. I'm not sure how to put it into words, but it' something like "concave" up, concave down, up, down, from top to bottom. In any case I'm sure I put them back the way I found them
I'm fairly certain that I didn't make a false statement about the number of disc springs but if I did I apologize and you were correct to point it out. There's way too much bad information available already.
I've attached two images, one showing the schematic of the first stages with a side-image that shows the same diagram but with only four Bellevilles. I do not seem to have a schematic for my 1983 Magnums (SRB3300) but the only difference I found is the number of Bellevilles. The schematic is for the Magnum II, Blizzard, Oasis, etc. The other image is the schematic for the Maximus, which shows five and I intend to put five in there. I suppose I could try to count the pieces and determine if there were five originally. If you happen to have a schematic for the original Magnum first stages please post it
I will try to get some photos either today or tomorrow of at least one Magnum first stage but I happen to be in the middle of another project at the moment. Somewhere I must have the manual for the early SRB3300 but perhaps it's on an old computer and I forgot to transfer the file. I usually print out this sort of thing but it might have been one of those "the printer just died" days.
Thanks for mentioning that Sherwood may still carry the springs. I don't remember exactly but they didn't show up in my search but I must have looked for them on their web site. I will look again.
Hopefully the springs will arrive soon from Canada and this story will have a happy ending