Howdy Lymanites,
FYI, years ago one of the techs at Lyman told me how they operate the 55 for consistent loads. Here's how I operate mine based on that info:
1. start with lever down (I have a baffle installed)..
2. lift the lever briskly and then tap it against the stop 2 more times.
3. flip the knocker
4. rotate the lever down and tap against the stop 2 more times.
5. flip the knocker
I know that sounds like a lot but it really doesn't take much extra time and (if done consistently) generates fairly consistent loads.
It works for me.
Rev. Chase