I acquired a 35 Whelen improved in 2020. I discovered that the barrel hadn’t been set back during the improving. I ordered a Manson 35 Whelen Improved reamer. I then necked up a 280Ackley case to 35 caliber. I filled the case full of lead for a go guage. My friend then took the rifle and reamed out the chamber to the “35-280 Ackley “ or it can be called a skinny 35 Brown Whelen. My 35 Whelen improved dies are set for the 35-280 Ackley, and the rifle shoots great.
