I'd have to say .400 Nitro that from some of the pictures and comments I've seen and heard, he ( SDH ) does some pretty fine rifle work as well.
Conventional rifles and double rifles are very distant relatives.
The lug issue with beavertails in shotguns is usually encountered in high volume shooting and seems to be a function of cycles. With heavy double rifles, the problem is raw recoil. Spend some time looking at double rifles in the repair shops. I've seen enough sheared lugs with beavertail fore-ends to not want such on one of mine.
