Standard barrel shank diameter on standard calibers are 1.055" x 20tpi. On the new WSM, RUM, and SAUM calibers it is 1.120" x 20tpi.

some times McGowen & others make a sharper higher VVVVVVVV point on the crest of there threads. Some have had to do a VERY, VERY LIGHT touch of a file or emery cloth.