I re-chambered a 35 Whelen to Brown-Whelen for a customer about thirty five years ago. Prior to re-chambering, he was getting about 2535 fps with 250's. After the re-chamber, he was getting 2580 with the same bullets. His main reason for doing it was that he had found some dies cheap. The rifle was a nice rifle as a Whelen and it was still a nice rifle as a Brown-Whelen. Back then, I think I charged him fifty bucks for the re-chamber so a little over a buck a foot in velocity increase. GD
