There is no right answer for the above question as it depends on the skill of the individual, one can do and other cannot. But considerable substance should be given to technology in scalping. Few years before scalping is a human (manual) job but now it is taken over by bots(computers,automation). Bots will spot the opportunity and execute the trade before human mind can digest the presented opportunity. I believe it is unwise to think that one can scalp and make consistent money manually.