Daryl,
As far as I remember it is a large rifle primer, but it may be small rifle. Just use which ever fits best. You are correct about the way the pin enters the primer. All pinfires are old. I don't think he has used smokeless, but was thinking about trying some different types, usually used by cowboy and black powder cartridge shooters. I would think you could also use black powder substitute ( I think one may be non fouling).