I got one of the first reamers available for the .204, and have built a number of them. Most folks are using them on coyotes; and very few have been happy with the way they perform on varmints this big. Some go down . . . some run off. This could very well be a bullet construction issue, since the .17 Remington kills coyotes fairly well and the .204 should work better . . . but the .22-250 and the .220 Swift are a surer thing on big varmints.