Problems with pvresize

Is it possible to resize a raw LVM partition (dev/sda7) that is 250 MB to 300 MB? I have tried using the pvresize command but fdisk is still showing /dev/sda7 as 250 MB. Pvdisplay shows the increase in the Physical Volume and Vol Group, but when I try expand my LV, it chokes out with a ioctl error and the LV stays the same size 250 M?

Dropping the partition and recreating with the proper size is not an option here, I need to maintain the data on the partition while Im resizing it. I can however, unmount the LVM I am trying to expand.

Thanks,