Some shooters like to lower the power of the gas ram in their rifle from time to time for easier cocking and quieter shooting, especially indoors. This gas ram handpump allows the shooter to bring a gas ram back up to full power. It is meant to be used with a chronograph so the velocity can be tested as you pump. It is a good idea to use the Straight Shooters Our Take test velocities as a guideline to avoid overcharging the gas ram.
It may also be used for gas ram rifles that have lost a little air over the years. Again, use the Our Take velocity numbers for the gun you own and the pellet being used as a guideline for full power velocity.