Both shots are aimed at the BG. The first shot is usually done with the .223 / 5.56. The bullet may fragment which is acceptable since it’s job is to break the glass. The second or kill shot if you will is aimed at the BG and the shot is fired immediately after the first one before the BG has a chance to realize what is happening and can react. The location of the hostages is always important. The ideal situation is the hostage(s) are not too close to the BG. A example is a bank robbery where all of the hostages are laying on floor and are several feet from the BG. The decision to shoot the BG should always be a last resort. There are several reasons why the order to shoot may be given. The BG starts killing the hostages, he refuses to talk with or stops talking to the negotiators, continuing to negotiate places the hostage(s) in more danger (for example a insulin dependent diabetic). I was offered a position on my department sniper team. Back then I could consistently put three rounds in a 1/2” group at 100 yards. The Team Commander was surprised when I turned the offer down as he knew I did a lot hunting. I explained to him my reason was if I flubbed a shot at a deer then all I have to do is track the wounded deer. However if I flubbed my shot on the BG then it is possible that he will kill the hostage(s) before the SWAT can enter the building / residence. I did not want that possibility hanging over my head.