Factorio Forums

normally when you place a blueprint, you can overlap existing buildings. But turrets cannot be overlapped if they are facing a different direction. It's not possible to work around this issue by always using (for example) north-facing turrets, because they will regularly point themselves in other directions when firing at enemies.

Thank you for the report, it is changed for 0.10.2 now.
The rule for the direction still works for all other entities like belts and inserters.