I highly doubt it's the inners. It must be the outer sleeve in the ball. As for the one that is stuck, I've had a shard of a pin stuck in the groove and it was extremely hard to get out. Also, if there is dried glue in the bottom of the hole, the newest inner sleeve can get lodged.
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Corey Clayton
Brunswick Amateur Staff
Turbo Grips Staff
Team Canada 2007, 2008, & 2009
All my equipment is professionally drilled by Rich Huzina at Strikes Pro Shop, Let's Bowl Calgary, AB
The opinions expressed are solely those of the writer and not of Brunswick Corporation