I just ordered some Norma brass to try with my 22/250. In your experience, which primers best fit this brass (i.e. not to tight or loose)?

I use CCI br2 primers in all my 22/250 loads.
I have not had any problems with primers in the 22/250. If you run max or over max loads you could stretch the pockets and have a loose primer fit. I have a batch of 100 winchester brass that i have reloaded 9 time to date. i FL resize and anneil the neck after ever 3rd. reload. the brass is still in good condition.
Dave

Since everyones primers and primer pockets are built to the same spec`s and tolerances; large rifle, small rifle, large pistol, ect, any primer will fit any brass. You might find a brand and style (br, mag) works better for your purpose but as far as one best for a cartridge, there isn`t one.
There may be a small difference in tightness depending on the primers or brass being on the high or low side of spec when built but there still is no cut and dry rule.