Brand new Lee Load Master
I'm almost too lazy to even post this but I figure it will help someone. But sorry I am definitely too lazy to take it all apart and take pics. And yes others have posted a fix for this somewhere I'm sure.
If you get a "smile" on your primers (I noticed mine on large primers), there is an easy fix.
First, lets ID what a smile is. After seating the primer, you inspect it, and notice that it seems to have a crescent, half moon, circular sort of impression on it. Like part of it got smashed.
On the Lee LoadMaster, the piston that drives the primer into the pocket is pushed upwards by a lever. This lever is the same one that the adjustable bolt for primer depth impacts.
Basically this lever is stamped steel, and the edges are not flat, because its stamped. So, this means that this non-flat edge, when pushing up on the piston that seats the primer, does not push straight up on it but tilts it. So you get an impression that is tilted (the smile).
To fix it, remove the primer parts, including the lever. The lever pivots on a special screw but its not hard to remove, just be gentle.
Then take a FINE file and carefully deburr/flatten both ends of the lever where it makes contact with the bolt and and piston. Only do it enough to remove the sharp edge or burr, and maintain the shape.
Reinstall and grease things very lightly (per the LEE manual)
You may also want to file down the surface of the adjustment bolt, since it probably has raised letters and this can contribute to putting non-normal forces on the lever.
This essentially eliminated the smiles on mine.
There is still slop in the system (the lever pivot has slop, the piston has slop in its cylinder), but this seemed to resolve things. Probably because the system tends to want to push the primer in straight.
Edit: I like my load master and this was an easy fix.