Energy Spectrum Capital, Dallas, through its current fund Energy Spectrum Partners IV LP, has invested $30 million in Oklahoma-based Forrest Drilling Co. LLC. Forrest is a start-up contract drilling company sponsored by Carl E. Gungoll Exploration LLC with five drilling rigs under construction contracts with deliveries throughout 2006. Forrest will initially operate in Mississippi, Texas and Oklahoma. Steve Hale, formerly president and chief operating officer of Bronco Drilling Co., is president of Forrest. Ramsey Drake will act as chief executive; Andrew Hunzicker will act as chief financial officer; Daniel Wilson will act as vice president of engineering; and Corry Woolington will act as business development manager. All are key senior managers from Gungoll.