4seventy:

I differ with Mac here slightly. It's possible he's right, but nobody has established it as fact. I know of rifles that both of those bullets have been fired in that show definite OSR, but they've also been fired with other monos that I know not to be safe. Who knows? Also, I've seen fired examples of both that definitely show that the full caliber shank has been engraved (the "ribs" not deep enough), which means to me that the design is flawed. A perfected design of that type or similar may very well be the "magic bullet", but it hasn't been done yet.

Heretofore, the manufacturers' final R & D "test" phase has been borne by the customers at the customers' risk and expense, and that just isn't acceptable when the manufacturer is making a specific recommendation that the bullet is appropriate for double rifle use, and no testing specific to double rifles has been done. Certainly lab testing needs to be done in turned down sacrificial barrels, but such testing is useless without additional testing in real double rifles that represent a cross section of the nitro rifles in common use today - in other words, both new and old. No manufacturer has ever done this. Until they do, having been their guinea pig once, I recommend against it.