Keep in mind that the seeding rate is purposely higher for lawns so that the higher plant density needed for lush lawns is achieved. A good final finish to planting a Bermudagrass lawn is to roll your planted lawn area with a hand roller. You can rent these implements from rental stores in your area. This compacts the soil around the seed, creating a more favorable environment for Bermudagrass seed germination. The rolling also smoothes the soil providing for a more level lawn.
Some seeds germinate faster and some take months longer.
Hulled seed generally germinate faster than un-hulled Bermuda seed. It all depends on the soil and climate for the period after you plant. Bermudagrass loves hot moist soil to germinate. That is when it will germinate the fastest. Keeping adequate moisture throughout the day is also a critical factor.