The default setting is 1000 buffers. Keep in mind that this is the shaping queue. Without any other configuration, the packets will then go to the interface software queue which may be FIFO and has its own queue length. Use show interface command to see output queue length of the interface queue.
show policy-map interface command will show the current shaping queue depth, but does not show the configured maximum.
command: shape max-buffers
To specify the maximum number of buffers allowed on shaping queues, use the shape max-buffers class-map configuration command. To remove the maximum number of buffers, use the no form of this command.
shape max-buffers "number-of-buffers"
no shape max-buffers "number-of-buffers"
Syntax Description
number-of-buffers
Specifies the maximum number of buffers. The minimum number of buffers is 1; the maximum number of buffers is 4096.
BTW if no Be is configured, the default is for Be=Bc
http://www.cisco.com/en/US/docs/ios/12_2/qos/command/reference/qrfcmd9.html