I have never had a BAR and decided to buy this one, I have other Browning rifles and shotguns. This BAR was made in 1989 s/n 137PN30374. I have been trying to find an operators manual for this rifle. All the manuals show and explain the bolt lock release lever on the right side of receiver by the forearm. This bar does not have a bolt release lock. How is best way to operate this rifle? Where can I find the operator's manual for this rifle. Thanks for any information.