Riv/Panaracer Jack Brown Mile Muncher Widths - undersized?

[Jim Schultz]

Hi friends  - 

Does anyone else have the 30mm or 33mm mile munchers? I found that my 30mm model treads are actually 28mm, and blow up to 28mm on a ~19.25mm inner width rim.

Strangely, i have had this issue with Panaracer tires before. Not sure if they all run undersized, as I was going to try and move up to 38mm. 

Thanks!

Jim