LME copper may correct about $300 in short-term as fundamentals haven't strengthened enough in past week to sustain recent rally, says trader at Japan house; LME 3-month copper up 8.5% since Mar. 15, last +$30 vs London PM kerb at $6,750/ton in very thin trade. Trader tips copper to target $6,400-$6,500; notes gains overnight largely driven by momentum trade, China copper data out yesterday shouldn't have been supportive factor as figures unchanged from preliminary data earlier in March.