When Field Testing a design in the various big-bore aiguns that are sent to us, we do not tether, nor do we refill after each shot if the particular Big-bore is not regulated, as we do not feel that would be how the big-bore airgun would be used in real world hunting situations. We also do not have the time to learn the particular Big-bore airguns sent to us: ideal starting fill pressure, “sweet spot”, best hold, its “likes/dislikes”, best power setting, power curve, etc. What we have learned, is that obtaining data on a designs accuracy and effectiveness, is that its always best when we send the Aeromunition round to be tested to the Field Testers that own their big-bore airgun… It is simply a lot better for everyone, as they do know their Big-bore’s vital information to obtain the most accurate results… Again because we do not have the time/luxury to learn this vital information, we set a goal of printing a group of no more than 2-inches to 3-inches at 100-yards, then figure that an airgunner that owns that particular big-bore airgun, should be able to tighten up the group, because they simply know their Big-bore. Hope that makes sense? Regardless, Happy Shooting and thanks again!