I don’t think I’d even try to inject primo 100 by itself. You’ve got to mix it with something mild like your test. And due to using EO I’ve found the WWB primo 200 to be, comparatively anyway, some of the least PIPish. But I always mix with at least equal volume of test 250 and sometimes something like nandrolone in the same syringe. As others have said, warming it helps too.
Avoid pinning primo 200 or any other high conc gear by itself. The whole purpose of getting HC gear is lower injection volumes so you can mix it with other stuff.