In a double, where two constrictions are available, improved cylinder and modified are a good pairing, especially in fixed-choke guns. If screw-in chokes are an option, try a more forgiving match, like skeet and light modified. Shoot the more open barrel first on the covey rise, then the tighter barrel as the birds make their escape.
The CD and DVD have a single track of data in the form of a spiral, which starts as the center going outwards. The data is stored on the bumps or pits which are then read by the CD/DVD layer. The bumps/pits on a DVD are much smaller than on CD, allowing the DVD to store more data.
A third difference has to do with the speed of the data retrieval from CDs and DVDs. The standard DVD will access stored data much more quickly than compact disks. Generally, the transfer rate for a CD is around 150KB per second. The typical DVD has a transfer rate that is roughly seven times greater. One final important difference between CDs and DVDs is the type of data that can be stored. UDF or Universal Data Format technology underpins DVD recording capacity. That means the DVD can store data, video, audio, or any combination of the three.