Speaking to Times Higher Education a year after the for-profit institution was awarded university college status, BPP's chief executive Carl Lygo said that the ratio would increase from an average of 7:1 to 14:1 or 15:1, and could reach 30:1 on some courses.
This compares with a national average of about 17:1, based on 2009-10 data and on staff who have teaching roles.
BPP currently has approximately 6,500 students, including 1,000 undergraduates, and it plans to open legal training centres in Cambridge and Liverpool in September.
Mr Lygo said the college was still in a "set-up phase", in which staff were not yet teaching 15 to 16 hours a week as they would in a more mature institution.
"Some courses have more staff than students at the moment," he said. "You can still have these kinds of (projected higher) ratios and maintain good teaching." He added that BPP planned to increase contact hours from 12-14 a week to 16.
In comparison with BPP's projected student-to-staff ratio of 14:1 or 15:1, rival private provider the College of Law's is 20:1, the ifs School of Finance's is close to 12:1, and the University of Buckingham's is 8:1.
With legal training courses opening in Bristol and Birmingham last year, and with its new law outposts set to open shortly, BPP is in a phase of rapid expansion after becoming the first private provider to win university college status in more than 30 years.
However, questions have been raised over the sustainability of this growth after BPP's US parent company, the Apollo Group, wrote $220 million (£135 million) off its value in March, following a $170.4 million write-down in October 2010.
At the time of the March devaluation, Apollo said BPP had "lower than expected" student numbers for finance and accountancy courses.
Sally Hunt, general secretary of the University and College Union, said: "BPP's belief that student-to-staff ratios of 30:1 are acceptable shows the pressure their American owners Apollo are now putting them under to deliver big profits from UK higher education."
Last month, BPP said it was cancelling plans to offer the Legal Practice Course (LPC) in Newcastle because of a lack of demand.
In 2010-11, enrolment on its LPC fell by 25 per cent to 1,563, it was reported, although the college said that this figure did not include the 280 students who joined the course in January and February.
There are also concerns that LPC places outstrip the number of training contracts available at legal firms.
Statistics from the Law Society indicate that there were 4,874 traineeships available in the year to 31 July 2010, while 15,164 LPC places were made available in 2010-11.
Judith Perkins, chair of the Junior Lawyers Division of the Law Society, said that expansion of LPC training places needed a "health warning" that they did not mean that the market for training contracts was picking up.
BPP said that across all of its law programmes, 91 per cent of graduates who responded to a survey were in full-time employment.