Kanye West has increased his lead over 50 Cent in the much scrutinized battle between the rap stars, according the Friday edition of Nielsen SoundScan's Building Charts.

Un-weighted sales from eight leading accounts through close of business yesterday (Sept. 13) show West's "Graduation" (Def Jam) increasing its lead over 50's "Curtis" (G-Unit/Interscope). The former now leads by 170,000 copies, compared to its margin of 127,000 on first-day sales.

West's newest posts 600,000 on the Friday chart, compared to 437,000 on the Wednesday Building Chart, which posted sales through Tuesday. The report also shows 50 Cent's set growing from 310,000 on the Wednesday chart to 430,000, while Kenny Chesney's "Just Who I Am: Poets and Pirates" more than doubles from 107,000 to 232,000. Despite the current sales tally, 50 Cent remained confident and weighed-in with Billboard.biz earlier today.

The numbers only reflect sales at the participating panel of Trans World Entertainment, Best Buy, Borders, Circuit City, iTunes, Target, Anderson Merchandisers and Handleman Co. The latter two companies place music in WalMart and other mass merchants.

SoundScan's newly launched Building Charts offer an indication of how each week's chart races are shaping up. The final charts, with sales from the entire panel extrapolated to reflect the overall U.S. market, are still released to SoundScan subscribers each Wednesday morning.