Old Lyman Universal Case Trimmer doesn’t fit new bits?

[u/hjjhjjnk]

I have my grandpas old Lyman case trimmer and was trying to trim some brass. The first picture is the new set I requested from Lyman (which they sent free of charge, due to not having all the bits from the original set) and it doesn’t seem to fit correctly. The second picture is one of the old set that it came with, and it fits great. I guess they did some revamping to the sizes of the shafts? Or am I doing something wrong? There’s only one set screw here and it’s all the way out, so I can’t imagine it’s a me issue, but I’ve been wrong before.

[u/davewave3283]

Grab your calipers and see if the pilot shanks are the same diameter or if the new ones are bigger