The opposite is happening in shares of $17.5 billion coating manufacturer PPG Industries ( PPG). Shares of the large-cap firm have rallied more than 37% so far in 2012, easily outperforming the rest of the market over the same time period. And an uptrending channel indicates that the rally isn't over yet -- only correcting this week. Like the broad market, PPG is correcting, giving back some gains as traders take a breather to absorb some of the gains that this stock has enjoyed. As long as shares stay above their trendline support level, the uptrend is still intact. >>5 Metals Stocks to Trade for Gains This Fall In fact, the ideal time to buy is a bounce off of support -- it's the price where shares have the furthest to move up to resistance, and it's the price with the least downside risk. A move below support means that the trend channel is broken and the trade is off; that's a logical place to put a protective stop under. Momentum adds some extra evidence to this trade too. The RSI line has been in an uptrend since the middle of May, which means that despite the correction, shares of PPG are still climbing at an increasing rate. Since momentum is a leading indicator of price, that's a very good sign.