HONG KONG (AP) — Chinese manufacturing activity ticked up more slowly than expected in September. A survey by HSBC Corp. released Monday showed that manufacturing activity in the world's No. 2 economy expanded slightly this month, rising to 50.2 from August's 50.1. The index uses a 100-point scale on which numbers below 50 indicate contraction. The reading was lower than the expected number of 51.2 from a preliminary version of the survey earlier this month. It's a sign China's gradual recovery from an extended slowdown could be more fragile than thought. But HSBC economists said the reading was still positive because it showed further improvement. China's leaders are trying to reverse a slowdown that dragged down growth to a two-decade low of 7.5 percent in the latest quarter.