I tested 158 gr lead in my 6" 686 with HS-6 a while back with
standard primers, cci500, since that was all I had at the time.

I got good accuracy and average fps with my loads but a few
looked like I was using black powder, with all the white smoke.

However the 158gr XTP with the cci550 primer in 38 and 357
magnum did not have any more smoke than a normal load but
I don't know if it was because of the copper jacket.
I have not shot any lead loads with the mag primers yet.