Samba 4 permission problem, force user/group

Samba is configured to use user 'torrent' and group 'users' for guest access. I am not able to alter directory and its contents without them having g+w permissions. I'd like to have this directory writable without g+w permissions. What am i missing ? My smb.conf: [global] security = user map to guest = bad user guest account = torrent [WDC_1T] comment = -- WDC 1TB -- path = /mnt/WDC_1T read only = no writeable = yes guest only = yes guest ok = yes force user = torrent force group = users guest account = torrent create mask = 0644 force create mode = 0644 directory mask = 0755 force directory mode = 0755 created a directory via samba, everything works as supposed: ls -ld _TEST_OK_/ drwxrwxr-x 2 torrent users 4096 02-27 15:42 _TEST_OK_/ created a directory on linux, same permissions, except not writable by group -> no write access: ls -ld _TEST_PERMISSION_ERROR_/ drwxr-xr-x 2 torrent users 4096 02-27 15:40 _TEST_PERMISSION_ERROR_/ ls -lR _TEST_PERMISSION_ERROR_/ -rw-rw-r-- 1 torrent users 0 02-27 15:40 plik1.txt