I was shooting BH209 in my original Disc 50cal, I'm not sure which BP you have but mine had a recess in the face of the BP (powder side) and I never had any issues with ignition. IIRC the longer flame channels had ignition problems.
Just use the standard 209 shotshell primers.
You will need to keep an eye on the flame channel as BH209 will corrode it up to the point of failure. In my cleaning kit I kept a set of torch tip cleaners that I used to keep the flame channel cleaned out.
My knight liked 90grains by volume under most 250gn pills, YMMV.
The Barnes expanders were my preferred bullet for hunting.
In my experiences, BH209 will still cause some corrosion but no way remotely close to black powder and BP subs.
Great stuff, IMO much better than black.
I have since kicked the smoking habit, love the sweet smell of smokeless!
Hope this helps...