mp_weapons_allow_map_placed 1
This command should be forced by the map itself but you might need it somehow ...

Another bunch of commands you guys posted to train with bots targets :
sv_cheats 1; bot_kick; mp_autoteambalance 0; mp_limitteams 0; mp_startmoney 10000; mp_round_restart_delay 0; mp_buytime 3600; mp_freezetime 0; mp_respawn_on_death_ct 1; bot_join_after_player 1; bot_quota 19; bot_join_team CT; sv_infinite_ammo 2; mp_restartgame 1; bot_dont_shoot 1; mp_death_drop_grenade 0; mp_death_drop_gun 1; mp_death_drop_defuser 0