Yes easiest way to understand the BHO feature of the FAL/L1A1 is that every rifle (except for the very very very very last ones made by FN - and not exported) has a BHO. Each and everyone can be had to operate as a last round hold open or not. It is just a small pin that fits in the BHO body and projects into the magazine well and is then manipulated by the follower of an empty magazine. It was not an issue feature on the L1A1 here in Australia but was on the L2A1 here. Both my L1A1s were subsequently fitted with the pin so as to lock open on an empty magazine. It SHOULD not be used as a bolt release however, this is accomplished by "sling shotting" the charging handle...