[1] While transport of ore from Butte to Anaconda was central to the line's founding, the BA&P was chartered as a common carrier and carried passengers and general freight.

[1] When it first opened, the BA&P used steam locomotives to haul the ore, freight, and passenger trains, however the heavy daily use took its toll on the engines, and by 1910 alternative power sources were being sought.

Power was delivered from Great Falls, 125 mi (201 km) to the northeast, and converted from AC to DC via several substations along the railway.

Mr. John D. Ryan, principal owner of this road,[...] (says) that "the cost was within the original estimate, the operation has been an unqualified success and the economy at least 50% in excess of the promises of the engineers at the time the work was undertaken.

[1] The two passenger locomotives were outfitted with double pantographs, dual headlights, and were geared for a standard running speed of 45 mph (72 km/h) while pulling three coaches.

[1] In 1914 four more locomotives were ordered from General Electric; these were geared lower than the other freight units and intended to be used at slow speeds in the smelter and Butte mine yards.

[citation needed] The railroad lost much of its business following the closure of the Anaconda smelter, and was sold to a consortium of local investors and reconstituted as the Rarus Railway (reporting mark RARW) in 1985.