I would suggest trimming the cases. If you don't start with consistent cases, how can you get a consistent product ?

Once the brass is all a more consistent length, you can get a consistent crimp.

I trim all the "new to me" cases I get. Decap, tumble, size, trim/chamfer. It's somewhat of a pain, but normally, with straight-wall revolver cases, is something that needs done only once.

I use a Lee hand trimmer, and chuck the case holder into a cordless drill. It's cumbersome and slow, but it's cheap. I plan to replace this trimmer with something else in the future. I've only been using this method since the late 1980s, so I don't want to move too quickly to change it....

According to my notes, the Lee hand trimmer trims to 1.278".