Transport: Unloaded and in a locked trunk or locked case or other secure container. (
General Law - Part I, Title XX, Chapter 140, Section 131C)
Storage: Secured in a locked container or equipped with a tamper-resistant mechanical lock or other safety device, properly engaged so as to render such weapon inoperable by any person other than the owner or other lawfully authorized user (
General Law - Part I, Title XX, Chapter 140, Section 131L)
Transport after a purchase is the same as any other transport.
Concealed carrying to/from the range on a "target and hunting" restriction depends on what the licensing authority (in your case Boston PD) interprets the restriction to mean.