It may be more of a bullet seating depth issue, rather than a cartridge overall length issue.
Remember that when the COLs were created, they were based on the standard bullets in use at the time.
For the 9mm Luger, it was a 124gr FMJ with a long tapering nose.
I don't know the Berry's bullet you are using, but its possible that it could be under listed max COL, and still be seated too far forward to allow proper chambering in a specific gun.
Also be aware that as you seat the bullet deeper, you are changing the volume of the powder space, so an adjustment in the powder charge might be in order, as the 9mm Luger is not very forgiving in that regard.