Yes, it's pretty common new cambearings are tight.
Don't know about smallblocks, but big blocks, yes.
I do also what Bulldozer does; use an old cam, grind a few sharp diagonal slits in the bearing-surfaces and use it as a reamer to clearance the bearings.
Make sure the old cam is actually straight first of course.
Use oil in the process and only rotate the old cam 2 or 3 times at a time, clean the slits and check with the new cam if it fits and rotates freely.
