During the COLGS, special means of take will be allowed, including: electronic calls, unplugged shotguns, one-half hour after sunset shooting hours and no daily bag or possession limits. The Conservation Order and special means of take provisions are designed to increase harvest and allow hunters to help reduce the population of mid-continent light geese (snow, blue & Ross’). All other waterfowl regulations will apply, including use of federally approved nontoxic shot. All participants will be required to have in their possession while hunting, all necessary licenses, waterfowl stamps and a Harvest Information Program permit (HIP). The Oklahoma Department of Wildlife Conservation is required by federal regulation to estimate the harvest of light geese during the COLGS. Therefore, to participate in the COLGS hunters should provide the ODWC with their name, full mailing address and telephone number so that they may be contacted after the season with a harvest survey.
So it looks like you have to buy a license, a waterfowl stamp, and a HIP permit, then do the COLGS registration which is here:
Others have offered up a sighting of roughly 2 inches high at 100 yards as a good sighting scheme. In my own experience I have come to favor a sighting of 3.5 inches high at 100 yards. This allows for the individual to hold dead-on (directly in the middle of the top and bottom) the animal out to roughly 350 yards.
Magnum calibers such as the 7mm Remington and 300 Winchester will extend this slightly. At 400 yards I hold directly on the backbone of the animal. The drop at this range allows the...