Thread: 44/40 reloads ( therapy needed )

Ok, so I have a problem.
Actually, I have a few, but hopefully the one you guys can help with is my handloads.
Loaded up about 20-25 loads with different powder weights, using some previously fired
brass, that came with my Rossi.
All good, reloads went well, no probs. Multiple case types, incl Starline.
Treated myself to some new Starline brass, dies set exactly the same, crushed 2 cases, seating the projectiles.
WTF, the previously fired Starline brass loaded fine.
Loaded up another couple of previously fired cartridges ( after crushing the new ones) and they loaded fine
Doing my head in.
Why would the ‘old’ cases load fine, and the ‘new’ cases won’t ?