This seems like a very odd standard to use? I understand that you wanted to compare performances of different languages, that's great.
But if you actually wanted to get the job done idiomatically, the code is one short, simple line of Perl 6. The performance, while admittedly slower, is within the same order of magnitude as your Perl 5 version.
To me, this is the magic of Perl 6. Sure, if you want to use 16 lines of loopy integer-crunching code to calculate the first N primes and you care about speed, Perl 6 should not be your choice. On the other hand, if you'd prefer to say
(1..$N).grep(*.is-prime)
and get the answer back in reasonable speed, Perl 6 is perfect.