So far, .22LR, .22Mag, 9mm, .410, and .45LC have been fired. The .22’s are mild and can be enjoyed round after round. At 9mm and above, the recoil becomes more pronounced, but is still not uncomfortable. More barrels, driving holster, and another grip are on the way. Changing out barrels takes 30 seconds or less. The firearm is solid and built like a tank. Workmanship is top notch. Well done, Bond Arms.